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as per recent discussions. Invent SubTransactionIds that are managed like CommandIds (ie, counter is reset at start of each top transaction), and use these instead of TransactionIds to keep track of subtransaction status in those modules that need it. This means that a subtransaction does not need an XID unless it actually inserts/modifies rows in the database. Accordingly, don't assign it an XID nor take a lock on the XID until it tries to do that. This saves a lot of overhead for subtransactions that are only used for error recovery (eg plpgsql exceptions). Also, arrange to release a subtransaction's XID lock as soon as the subtransaction exits, in both the commit and abort cases. This avoids holding many unique locks after a long series of subtransactions. The price is some additional overhead in XactLockTableWait, but that seems acceptable. Finally, restructure the state machine in xact.c to have a more orthogonal set of states for subtransactions.
5613 lines
161 KiB
C
5613 lines
161 KiB
C
/*-------------------------------------------------------------------------
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*
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* xlog.c
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* PostgreSQL transaction log manager
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*
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*
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* Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.170 2004/09/16 16:58:26 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include <ctype.h>
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#include <fcntl.h>
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#include <signal.h>
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#include <time.h>
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#include <unistd.h>
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#include <sys/stat.h>
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#include <sys/time.h>
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#include "access/clog.h"
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#include "access/subtrans.h"
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#include "access/xact.h"
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#include "access/xlog.h"
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#include "access/xlog_internal.h"
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#include "access/xlogutils.h"
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#include "catalog/catversion.h"
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#include "catalog/pg_control.h"
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#include "miscadmin.h"
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#include "postmaster/bgwriter.h"
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#include "storage/bufpage.h"
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#include "storage/fd.h"
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#include "storage/lwlock.h"
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#include "storage/pmsignal.h"
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#include "storage/proc.h"
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#include "storage/sinval.h"
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#include "storage/spin.h"
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#include "utils/builtins.h"
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#include "utils/guc.h"
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#include "utils/relcache.h"
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/*
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* This chunk of hackery attempts to determine which file sync methods
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* are available on the current platform, and to choose an appropriate
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* default method. We assume that fsync() is always available, and that
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* configure determined whether fdatasync() is.
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*/
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#define SYNC_METHOD_FSYNC 0
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#define SYNC_METHOD_FDATASYNC 1
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#define SYNC_METHOD_OPEN 2 /* used for both O_SYNC and
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* O_DSYNC */
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#if defined(O_SYNC)
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#define OPEN_SYNC_FLAG O_SYNC
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#else
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#if defined(O_FSYNC)
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#define OPEN_SYNC_FLAG O_FSYNC
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#endif
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#endif
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#if defined(OPEN_SYNC_FLAG)
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#if defined(O_DSYNC) && (O_DSYNC != OPEN_SYNC_FLAG)
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#define OPEN_DATASYNC_FLAG O_DSYNC
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#endif
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#endif
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#if defined(OPEN_DATASYNC_FLAG)
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#define DEFAULT_SYNC_METHOD_STR "open_datasync"
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#define DEFAULT_SYNC_METHOD SYNC_METHOD_OPEN
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#define DEFAULT_SYNC_FLAGBIT OPEN_DATASYNC_FLAG
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#else
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#if defined(HAVE_FDATASYNC)
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#define DEFAULT_SYNC_METHOD_STR "fdatasync"
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#define DEFAULT_SYNC_METHOD SYNC_METHOD_FDATASYNC
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#define DEFAULT_SYNC_FLAGBIT 0
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#else
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#define DEFAULT_SYNC_METHOD_STR "fsync"
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#define DEFAULT_SYNC_METHOD SYNC_METHOD_FSYNC
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#define DEFAULT_SYNC_FLAGBIT 0
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#endif
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#endif
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/* User-settable parameters */
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int CheckPointSegments = 3;
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int XLOGbuffers = 8;
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char *XLogArchiveCommand = NULL;
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char *XLOG_sync_method = NULL;
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const char XLOG_sync_method_default[] = DEFAULT_SYNC_METHOD_STR;
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#ifdef WAL_DEBUG
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bool XLOG_DEBUG = false;
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#endif
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/*
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* XLOGfileslop is used in the code as the allowed "fuzz" in the number of
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* preallocated XLOG segments --- we try to have at least XLOGfiles advance
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* segments but no more than XLOGfileslop segments. This could
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* be made a separate GUC variable, but at present I think it's sufficient
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* to hardwire it as 2*CheckPointSegments+1. Under normal conditions, a
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* checkpoint will free no more than 2*CheckPointSegments log segments, and
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* we want to recycle all of them; the +1 allows boundary cases to happen
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* without wasting a delete/create-segment cycle.
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*/
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#define XLOGfileslop (2*CheckPointSegments + 1)
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/* these are derived from XLOG_sync_method by assign_xlog_sync_method */
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static int sync_method = DEFAULT_SYNC_METHOD;
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static int open_sync_bit = DEFAULT_SYNC_FLAGBIT;
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#define XLOG_SYNC_BIT (enableFsync ? open_sync_bit : 0)
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#define MinXLOGbuffers 4
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/*
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* ThisTimeLineID will be same in all backends --- it identifies current
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* WAL timeline for the database system.
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*/
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TimeLineID ThisTimeLineID = 0;
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/* Are we doing recovery from XLOG? */
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bool InRecovery = false;
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/* Are we recovering using offline XLOG archives? */
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static bool InArchiveRecovery = false;
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/* Was the last xlog file restored from archive, or local? */
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static bool restoredFromArchive = false;
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/* options taken from recovery.conf */
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static char *recoveryRestoreCommand = NULL;
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static bool recoveryTarget = false;
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static bool recoveryTargetExact = false;
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static bool recoveryTargetInclusive = true;
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static TransactionId recoveryTargetXid;
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static time_t recoveryTargetTime;
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/* if recoveryStopsHere returns true, it saves actual stop xid/time here */
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static TransactionId recoveryStopXid;
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static time_t recoveryStopTime;
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static bool recoveryStopAfter;
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/* constraint set by read_backup_label */
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static XLogRecPtr recoveryMinXlogOffset = {0, 0};
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/*
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* During normal operation, the only timeline we care about is ThisTimeLineID.
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* During recovery, however, things are more complicated. To simplify life
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* for rmgr code, we keep ThisTimeLineID set to the "current" timeline as we
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* scan through the WAL history (that is, it is the line that was active when
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* the currently-scanned WAL record was generated). We also need these
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* timeline values:
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*
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* recoveryTargetTLI: the desired timeline that we want to end in.
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*
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* expectedTLIs: an integer list of recoveryTargetTLI and the TLIs of
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* its known parents, newest first (so recoveryTargetTLI is always the
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* first list member). Only these TLIs are expected to be seen in the WAL
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* segments we read, and indeed only these TLIs will be considered as
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* candidate WAL files to open at all.
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*
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* curFileTLI: the TLI appearing in the name of the current input WAL file.
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* (This is not necessarily the same as ThisTimeLineID, because we could
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* be scanning data that was copied from an ancestor timeline when the current
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* file was created.) During a sequential scan we do not allow this value
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* to decrease.
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*/
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static TimeLineID recoveryTargetTLI;
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static List *expectedTLIs;
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static TimeLineID curFileTLI;
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/*
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* MyLastRecPtr points to the start of the last XLOG record inserted by the
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* current transaction. If MyLastRecPtr.xrecoff == 0, then the current
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* xact hasn't yet inserted any transaction-controlled XLOG records.
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*
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* Note that XLOG records inserted outside transaction control are not
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* reflected into MyLastRecPtr. They do, however, cause MyXactMadeXLogEntry
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* to be set true. The latter can be used to test whether the current xact
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* made any loggable changes (including out-of-xact changes, such as
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* sequence updates).
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*
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* When we insert/update/delete a tuple in a temporary relation, we do not
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* make any XLOG record, since we don't care about recovering the state of
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* the temp rel after a crash. However, we will still need to remember
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* whether our transaction committed or aborted in that case. So, we must
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* set MyXactMadeTempRelUpdate true to indicate that the XID will be of
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* interest later.
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*/
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XLogRecPtr MyLastRecPtr = {0, 0};
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bool MyXactMadeXLogEntry = false;
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bool MyXactMadeTempRelUpdate = false;
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/*
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* ProcLastRecPtr points to the start of the last XLOG record inserted by the
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* current backend. It is updated for all inserts, transaction-controlled
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* or not. ProcLastRecEnd is similar but points to end+1 of last record.
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*/
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static XLogRecPtr ProcLastRecPtr = {0, 0};
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XLogRecPtr ProcLastRecEnd = {0, 0};
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/*
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* RedoRecPtr is this backend's local copy of the REDO record pointer
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* (which is almost but not quite the same as a pointer to the most recent
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* CHECKPOINT record). We update this from the shared-memory copy,
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* XLogCtl->Insert.RedoRecPtr, whenever we can safely do so (ie, when we
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* hold the Insert lock). See XLogInsert for details. We are also allowed
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* to update from XLogCtl->Insert.RedoRecPtr if we hold the info_lck;
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* see GetRedoRecPtr. A freshly spawned backend obtains the value during
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* InitXLOGAccess.
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*/
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static XLogRecPtr RedoRecPtr;
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/*----------
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* Shared-memory data structures for XLOG control
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*
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* LogwrtRqst indicates a byte position that we need to write and/or fsync
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* the log up to (all records before that point must be written or fsynced).
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* LogwrtResult indicates the byte positions we have already written/fsynced.
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* These structs are identical but are declared separately to indicate their
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* slightly different functions.
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*
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* We do a lot of pushups to minimize the amount of access to lockable
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* shared memory values. There are actually three shared-memory copies of
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* LogwrtResult, plus one unshared copy in each backend. Here's how it works:
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* XLogCtl->LogwrtResult is protected by info_lck
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* XLogCtl->Write.LogwrtResult is protected by WALWriteLock
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* XLogCtl->Insert.LogwrtResult is protected by WALInsertLock
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* One must hold the associated lock to read or write any of these, but
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* of course no lock is needed to read/write the unshared LogwrtResult.
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*
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* XLogCtl->LogwrtResult and XLogCtl->Write.LogwrtResult are both "always
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* right", since both are updated by a write or flush operation before
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* it releases WALWriteLock. The point of keeping XLogCtl->Write.LogwrtResult
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* is that it can be examined/modified by code that already holds WALWriteLock
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* without needing to grab info_lck as well.
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*
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* XLogCtl->Insert.LogwrtResult may lag behind the reality of the other two,
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* but is updated when convenient. Again, it exists for the convenience of
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* code that is already holding WALInsertLock but not the other locks.
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*
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* The unshared LogwrtResult may lag behind any or all of these, and again
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* is updated when convenient.
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*
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* The request bookkeeping is simpler: there is a shared XLogCtl->LogwrtRqst
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* (protected by info_lck), but we don't need to cache any copies of it.
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*
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* Note that this all works because the request and result positions can only
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* advance forward, never back up, and so we can easily determine which of two
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* values is "more up to date".
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*
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* info_lck is only held long enough to read/update the protected variables,
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* so it's a plain spinlock. The other locks are held longer (potentially
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* over I/O operations), so we use LWLocks for them. These locks are:
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*
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* WALInsertLock: must be held to insert a record into the WAL buffers.
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*
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* WALWriteLock: must be held to write WAL buffers to disk (XLogWrite or
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* XLogFlush).
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*
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* ControlFileLock: must be held to read/update control file or create
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* new log file.
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*
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* CheckpointLock: must be held to do a checkpoint (ensures only one
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* checkpointer at a time; even though the postmaster won't launch
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* parallel checkpoint processes, we need this because manual checkpoints
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* could be launched simultaneously).
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*
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*----------
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*/
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typedef struct XLogwrtRqst
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{
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XLogRecPtr Write; /* last byte + 1 to write out */
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XLogRecPtr Flush; /* last byte + 1 to flush */
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} XLogwrtRqst;
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typedef struct XLogwrtResult
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{
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XLogRecPtr Write; /* last byte + 1 written out */
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XLogRecPtr Flush; /* last byte + 1 flushed */
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} XLogwrtResult;
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/*
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* Shared state data for XLogInsert.
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*/
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typedef struct XLogCtlInsert
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{
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XLogwrtResult LogwrtResult; /* a recent value of LogwrtResult */
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XLogRecPtr PrevRecord; /* start of previously-inserted record */
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uint16 curridx; /* current block index in cache */
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XLogPageHeader currpage; /* points to header of block in cache */
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char *currpos; /* current insertion point in cache */
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XLogRecPtr RedoRecPtr; /* current redo point for insertions */
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} XLogCtlInsert;
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/*
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* Shared state data for XLogWrite/XLogFlush.
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*/
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typedef struct XLogCtlWrite
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{
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XLogwrtResult LogwrtResult; /* current value of LogwrtResult */
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uint16 curridx; /* cache index of next block to write */
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} XLogCtlWrite;
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/*
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* Total shared-memory state for XLOG.
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*/
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typedef struct XLogCtlData
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{
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/* Protected by WALInsertLock: */
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XLogCtlInsert Insert;
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/* Protected by info_lck: */
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XLogwrtRqst LogwrtRqst;
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XLogwrtResult LogwrtResult;
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/* Protected by WALWriteLock: */
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XLogCtlWrite Write;
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/*
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* These values do not change after startup, although the pointed-to
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* pages and xlblocks values certainly do. Permission to read/write
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* the pages and xlblocks values depends on WALInsertLock and
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* WALWriteLock.
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*/
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char *pages; /* buffers for unwritten XLOG pages */
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XLogRecPtr *xlblocks; /* 1st byte ptr-s + BLCKSZ */
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uint32 XLogCacheByte; /* # bytes in xlog buffers */
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uint32 XLogCacheBlck; /* highest allocated xlog buffer index */
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TimeLineID ThisTimeLineID;
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slock_t info_lck; /* locks shared LogwrtRqst/LogwrtResult */
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} XLogCtlData;
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static XLogCtlData *XLogCtl = NULL;
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/*
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* We maintain an image of pg_control in shared memory.
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*/
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static ControlFileData *ControlFile = NULL;
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/*
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* Macros for managing XLogInsert state. In most cases, the calling routine
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* has local copies of XLogCtl->Insert and/or XLogCtl->Insert->curridx,
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* so these are passed as parameters instead of being fetched via XLogCtl.
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*/
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/* Free space remaining in the current xlog page buffer */
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#define INSERT_FREESPACE(Insert) \
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(BLCKSZ - ((Insert)->currpos - (char *) (Insert)->currpage))
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/* Construct XLogRecPtr value for current insertion point */
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#define INSERT_RECPTR(recptr,Insert,curridx) \
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( \
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(recptr).xlogid = XLogCtl->xlblocks[curridx].xlogid, \
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(recptr).xrecoff = \
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XLogCtl->xlblocks[curridx].xrecoff - INSERT_FREESPACE(Insert) \
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)
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#define PrevBufIdx(idx) \
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(((idx) == 0) ? XLogCtl->XLogCacheBlck : ((idx) - 1))
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#define NextBufIdx(idx) \
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(((idx) == XLogCtl->XLogCacheBlck) ? 0 : ((idx) + 1))
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/* File path names */
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char XLogDir[MAXPGPATH];
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static char ControlFilePath[MAXPGPATH];
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/*
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* Private, possibly out-of-date copy of shared LogwrtResult.
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* See discussion above.
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*/
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static XLogwrtResult LogwrtResult = {{0, 0}, {0, 0}};
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/*
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* openLogFile is -1 or a kernel FD for an open log file segment.
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* When it's open, openLogOff is the current seek offset in the file.
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* openLogId/openLogSeg identify the segment. These variables are only
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* used to write the XLOG, and so will normally refer to the active segment.
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*/
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static int openLogFile = -1;
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static uint32 openLogId = 0;
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static uint32 openLogSeg = 0;
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static uint32 openLogOff = 0;
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/*
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* These variables are used similarly to the ones above, but for reading
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* the XLOG. Note, however, that readOff generally represents the offset
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* of the page just read, not the seek position of the FD itself, which
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* will be just past that page.
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*/
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static int readFile = -1;
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static uint32 readId = 0;
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static uint32 readSeg = 0;
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static uint32 readOff = 0;
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/* Buffer for currently read page (BLCKSZ bytes) */
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static char *readBuf = NULL;
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/* Buffer for current ReadRecord result (expandable) */
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static char *readRecordBuf = NULL;
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static uint32 readRecordBufSize = 0;
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/* State information for XLOG reading */
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static XLogRecPtr ReadRecPtr;
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static XLogRecPtr EndRecPtr;
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static XLogRecord *nextRecord = NULL;
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static TimeLineID lastPageTLI = 0;
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static bool InRedo = false;
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static void XLogArchiveNotify(const char *xlog);
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static void XLogArchiveNotifySeg(uint32 log, uint32 seg);
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static bool XLogArchiveIsDone(const char *xlog);
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static void XLogArchiveCleanup(const char *xlog);
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static void readRecoveryCommandFile(void);
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static void exitArchiveRecovery(TimeLineID endTLI,
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uint32 endLogId, uint32 endLogSeg);
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static bool recoveryStopsHere(XLogRecord *record, bool *includeThis);
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static bool AdvanceXLInsertBuffer(void);
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static void XLogWrite(XLogwrtRqst WriteRqst);
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static int XLogFileInit(uint32 log, uint32 seg,
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bool *use_existent, bool use_lock);
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static bool InstallXLogFileSegment(uint32 log, uint32 seg, char *tmppath,
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bool find_free, int max_advance,
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bool use_lock);
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static int XLogFileOpen(uint32 log, uint32 seg);
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static int XLogFileRead(uint32 log, uint32 seg, int emode);
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static bool RestoreArchivedFile(char *path, const char *xlogfname,
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const char *recovername, off_t expectedSize);
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static void PreallocXlogFiles(XLogRecPtr endptr);
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static void MoveOfflineLogs(uint32 log, uint32 seg, XLogRecPtr endptr);
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static XLogRecord *ReadRecord(XLogRecPtr *RecPtr, int emode);
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static bool ValidXLOGHeader(XLogPageHeader hdr, int emode);
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static XLogRecord *ReadCheckpointRecord(XLogRecPtr RecPtr, int whichChkpt);
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static List *readTimeLineHistory(TimeLineID targetTLI);
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static bool existsTimeLineHistory(TimeLineID probeTLI);
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static TimeLineID findNewestTimeLine(TimeLineID startTLI);
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static void writeTimeLineHistory(TimeLineID newTLI, TimeLineID parentTLI,
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TimeLineID endTLI,
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uint32 endLogId, uint32 endLogSeg);
|
|
static void WriteControlFile(void);
|
|
static void ReadControlFile(void);
|
|
static char *str_time(time_t tnow);
|
|
static void issue_xlog_fsync(void);
|
|
|
|
#ifdef WAL_DEBUG
|
|
static void xlog_outrec(char *buf, XLogRecord *record);
|
|
#endif
|
|
static bool read_backup_label(XLogRecPtr *checkPointLoc);
|
|
static void remove_backup_label(void);
|
|
|
|
|
|
/*
|
|
* Insert an XLOG record having the specified RMID and info bytes,
|
|
* with the body of the record being the data chunk(s) described by
|
|
* the rdata list (see xlog.h for notes about rdata).
|
|
*
|
|
* Returns XLOG pointer to end of record (beginning of next record).
|
|
* This can be used as LSN for data pages affected by the logged action.
|
|
* (LSN is the XLOG point up to which the XLOG must be flushed to disk
|
|
* before the data page can be written out. This implements the basic
|
|
* WAL rule "write the log before the data".)
|
|
*
|
|
* NB: this routine feels free to scribble on the XLogRecData structs,
|
|
* though not on the data they reference. This is OK since the XLogRecData
|
|
* structs are always just temporaries in the calling code.
|
|
*/
|
|
XLogRecPtr
|
|
XLogInsert(RmgrId rmid, uint8 info, XLogRecData *rdata)
|
|
{
|
|
XLogCtlInsert *Insert = &XLogCtl->Insert;
|
|
XLogRecord *record;
|
|
XLogContRecord *contrecord;
|
|
XLogRecPtr RecPtr;
|
|
XLogRecPtr WriteRqst;
|
|
uint32 freespace;
|
|
uint16 curridx;
|
|
XLogRecData *rdt;
|
|
Buffer dtbuf[XLR_MAX_BKP_BLOCKS];
|
|
bool dtbuf_bkp[XLR_MAX_BKP_BLOCKS];
|
|
BkpBlock dtbuf_xlg[XLR_MAX_BKP_BLOCKS];
|
|
XLogRecPtr dtbuf_lsn[XLR_MAX_BKP_BLOCKS];
|
|
XLogRecData dtbuf_rdt[2 * XLR_MAX_BKP_BLOCKS];
|
|
crc64 rdata_crc;
|
|
uint32 len,
|
|
write_len;
|
|
unsigned i;
|
|
XLogwrtRqst LogwrtRqst;
|
|
bool updrqst;
|
|
bool no_tran = (rmid == RM_XLOG_ID) ? true : false;
|
|
|
|
if (info & XLR_INFO_MASK)
|
|
{
|
|
if ((info & XLR_INFO_MASK) != XLOG_NO_TRAN)
|
|
elog(PANIC, "invalid xlog info mask %02X", (info & XLR_INFO_MASK));
|
|
no_tran = true;
|
|
info &= ~XLR_INFO_MASK;
|
|
}
|
|
|
|
/*
|
|
* In bootstrap mode, we don't actually log anything but XLOG
|
|
* resources; return a phony record pointer.
|
|
*/
|
|
if (IsBootstrapProcessingMode() && rmid != RM_XLOG_ID)
|
|
{
|
|
RecPtr.xlogid = 0;
|
|
RecPtr.xrecoff = SizeOfXLogLongPHD; /* start of 1st chkpt
|
|
* record */
|
|
return (RecPtr);
|
|
}
|
|
|
|
/*
|
|
* Here we scan the rdata list, determine which buffers must be backed
|
|
* up, and compute the CRC values for the data. Note that the record
|
|
* header isn't added into the CRC yet since we don't know the final
|
|
* length or info bits quite yet.
|
|
*
|
|
* We may have to loop back to here if a race condition is detected
|
|
* below. We could prevent the race by doing all this work while
|
|
* holding the insert lock, but it seems better to avoid doing CRC
|
|
* calculations while holding the lock. This means we have to be
|
|
* careful about modifying the rdata list until we know we aren't
|
|
* going to loop back again. The only change we allow ourselves to
|
|
* make earlier is to set rdt->data = NULL in list items we have
|
|
* decided we will have to back up the whole buffer for. This is OK
|
|
* because we will certainly decide the same thing again for those
|
|
* items if we do it over; doing it here saves an extra pass over the
|
|
* list later.
|
|
*/
|
|
begin:;
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
dtbuf[i] = InvalidBuffer;
|
|
dtbuf_bkp[i] = false;
|
|
}
|
|
|
|
INIT_CRC64(rdata_crc);
|
|
len = 0;
|
|
for (rdt = rdata;;)
|
|
{
|
|
if (rdt->buffer == InvalidBuffer)
|
|
{
|
|
/* Simple data, just include it */
|
|
len += rdt->len;
|
|
COMP_CRC64(rdata_crc, rdt->data, rdt->len);
|
|
}
|
|
else
|
|
{
|
|
/* Find info for buffer */
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (rdt->buffer == dtbuf[i])
|
|
{
|
|
/* Buffer already referenced by earlier list item */
|
|
if (dtbuf_bkp[i])
|
|
rdt->data = NULL;
|
|
else if (rdt->data)
|
|
{
|
|
len += rdt->len;
|
|
COMP_CRC64(rdata_crc, rdt->data, rdt->len);
|
|
}
|
|
break;
|
|
}
|
|
if (dtbuf[i] == InvalidBuffer)
|
|
{
|
|
/* OK, put it in this slot */
|
|
dtbuf[i] = rdt->buffer;
|
|
|
|
/*
|
|
* XXX We assume page LSN is first data on page
|
|
*/
|
|
dtbuf_lsn[i] = *((XLogRecPtr *) BufferGetBlock(rdt->buffer));
|
|
if (XLByteLE(dtbuf_lsn[i], RedoRecPtr))
|
|
{
|
|
crc64 dtcrc;
|
|
|
|
dtbuf_bkp[i] = true;
|
|
rdt->data = NULL;
|
|
INIT_CRC64(dtcrc);
|
|
COMP_CRC64(dtcrc,
|
|
BufferGetBlock(dtbuf[i]),
|
|
BLCKSZ);
|
|
dtbuf_xlg[i].node = BufferGetFileNode(dtbuf[i]);
|
|
dtbuf_xlg[i].block = BufferGetBlockNumber(dtbuf[i]);
|
|
COMP_CRC64(dtcrc,
|
|
(char *) &(dtbuf_xlg[i]) + sizeof(crc64),
|
|
sizeof(BkpBlock) - sizeof(crc64));
|
|
FIN_CRC64(dtcrc);
|
|
dtbuf_xlg[i].crc = dtcrc;
|
|
}
|
|
else if (rdt->data)
|
|
{
|
|
len += rdt->len;
|
|
COMP_CRC64(rdata_crc, rdt->data, rdt->len);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
if (i >= XLR_MAX_BKP_BLOCKS)
|
|
elog(PANIC, "can backup at most %d blocks per xlog record",
|
|
XLR_MAX_BKP_BLOCKS);
|
|
}
|
|
/* Break out of loop when rdt points to last list item */
|
|
if (rdt->next == NULL)
|
|
break;
|
|
rdt = rdt->next;
|
|
}
|
|
|
|
/*
|
|
* NOTE: the test for len == 0 here is somewhat fishy, since in theory
|
|
* all of the rmgr data might have been suppressed in favor of backup
|
|
* blocks. Currently, all callers of XLogInsert provide at least some
|
|
* not-in-a-buffer data and so len == 0 should never happen, but that
|
|
* may not be true forever. If you need to remove the len == 0 check,
|
|
* also remove the check for xl_len == 0 in ReadRecord, below.
|
|
*/
|
|
if (len == 0)
|
|
elog(PANIC, "invalid xlog record length %u", len);
|
|
|
|
START_CRIT_SECTION();
|
|
|
|
/* update LogwrtResult before doing cache fill check */
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
LogwrtRqst = xlogctl->LogwrtRqst;
|
|
LogwrtResult = xlogctl->LogwrtResult;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
}
|
|
|
|
/*
|
|
* If cache is half filled then try to acquire write lock and do
|
|
* XLogWrite. Ignore any fractional blocks in performing this check.
|
|
*/
|
|
LogwrtRqst.Write.xrecoff -= LogwrtRqst.Write.xrecoff % BLCKSZ;
|
|
if (LogwrtRqst.Write.xlogid != LogwrtResult.Write.xlogid ||
|
|
(LogwrtRqst.Write.xrecoff >= LogwrtResult.Write.xrecoff +
|
|
XLogCtl->XLogCacheByte / 2))
|
|
{
|
|
if (LWLockConditionalAcquire(WALWriteLock, LW_EXCLUSIVE))
|
|
{
|
|
LogwrtResult = XLogCtl->Write.LogwrtResult;
|
|
if (XLByteLT(LogwrtResult.Write, LogwrtRqst.Write))
|
|
XLogWrite(LogwrtRqst);
|
|
LWLockRelease(WALWriteLock);
|
|
}
|
|
}
|
|
|
|
/* Now wait to get insert lock */
|
|
LWLockAcquire(WALInsertLock, LW_EXCLUSIVE);
|
|
|
|
/*
|
|
* Check to see if my RedoRecPtr is out of date. If so, may have to
|
|
* go back and recompute everything. This can only happen just after
|
|
* a checkpoint, so it's better to be slow in this case and fast
|
|
* otherwise.
|
|
*/
|
|
if (!XLByteEQ(RedoRecPtr, Insert->RedoRecPtr))
|
|
{
|
|
Assert(XLByteLT(RedoRecPtr, Insert->RedoRecPtr));
|
|
RedoRecPtr = Insert->RedoRecPtr;
|
|
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (dtbuf[i] == InvalidBuffer)
|
|
continue;
|
|
if (dtbuf_bkp[i] == false &&
|
|
XLByteLE(dtbuf_lsn[i], RedoRecPtr))
|
|
{
|
|
/*
|
|
* Oops, this buffer now needs to be backed up, but we
|
|
* didn't think so above. Start over.
|
|
*/
|
|
LWLockRelease(WALInsertLock);
|
|
END_CRIT_SECTION();
|
|
goto begin;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Make additional rdata list entries for the backup blocks, so that
|
|
* we don't need to special-case them in the write loop. Note that we
|
|
* have now irrevocably changed the input rdata list. At the exit of
|
|
* this loop, write_len includes the backup block data.
|
|
*
|
|
* Also set the appropriate info bits to show which buffers were backed
|
|
* up. The i'th XLR_SET_BKP_BLOCK bit corresponds to the i'th
|
|
* distinct buffer value (ignoring InvalidBuffer) appearing in the
|
|
* rdata list.
|
|
*/
|
|
write_len = len;
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (dtbuf[i] == InvalidBuffer || !(dtbuf_bkp[i]))
|
|
continue;
|
|
|
|
info |= XLR_SET_BKP_BLOCK(i);
|
|
|
|
rdt->next = &(dtbuf_rdt[2 * i]);
|
|
|
|
dtbuf_rdt[2 * i].data = (char *) &(dtbuf_xlg[i]);
|
|
dtbuf_rdt[2 * i].len = sizeof(BkpBlock);
|
|
write_len += sizeof(BkpBlock);
|
|
|
|
rdt = dtbuf_rdt[2 * i].next = &(dtbuf_rdt[2 * i + 1]);
|
|
|
|
dtbuf_rdt[2 * i + 1].data = (char *) BufferGetBlock(dtbuf[i]);
|
|
dtbuf_rdt[2 * i + 1].len = BLCKSZ;
|
|
write_len += BLCKSZ;
|
|
dtbuf_rdt[2 * i + 1].next = NULL;
|
|
}
|
|
|
|
/*
|
|
* If there isn't enough space on the current XLOG page for a record
|
|
* header, advance to the next page (leaving the unused space as
|
|
* zeroes).
|
|
*/
|
|
updrqst = false;
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
if (freespace < SizeOfXLogRecord)
|
|
{
|
|
updrqst = AdvanceXLInsertBuffer();
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
}
|
|
|
|
curridx = Insert->curridx;
|
|
record = (XLogRecord *) Insert->currpos;
|
|
|
|
/* Insert record header */
|
|
|
|
record->xl_prev = Insert->PrevRecord;
|
|
record->xl_xid = GetCurrentTransactionIdIfAny();
|
|
record->xl_len = len; /* doesn't include backup blocks */
|
|
record->xl_info = info;
|
|
record->xl_rmid = rmid;
|
|
|
|
/* Now we can finish computing the main CRC */
|
|
COMP_CRC64(rdata_crc, (char *) record + sizeof(crc64),
|
|
SizeOfXLogRecord - sizeof(crc64));
|
|
FIN_CRC64(rdata_crc);
|
|
record->xl_crc = rdata_crc;
|
|
|
|
/* Compute record's XLOG location */
|
|
INSERT_RECPTR(RecPtr, Insert, curridx);
|
|
|
|
/* If first XLOG record of transaction, save it in PGPROC array */
|
|
if (MyLastRecPtr.xrecoff == 0 && !no_tran)
|
|
{
|
|
/*
|
|
* We do not acquire SInvalLock here because of possible deadlock.
|
|
* Anyone who wants to inspect other procs' logRec must acquire
|
|
* WALInsertLock, instead. A better solution would be a per-PROC
|
|
* spinlock, but no time for that before 7.2 --- tgl 12/19/01.
|
|
*/
|
|
MyProc->logRec = RecPtr;
|
|
}
|
|
|
|
#ifdef WAL_DEBUG
|
|
if (XLOG_DEBUG)
|
|
{
|
|
char buf[8192];
|
|
|
|
sprintf(buf, "INSERT @ %X/%X: ", RecPtr.xlogid, RecPtr.xrecoff);
|
|
xlog_outrec(buf, record);
|
|
if (rdata->data != NULL)
|
|
{
|
|
strcat(buf, " - ");
|
|
RmgrTable[record->xl_rmid].rm_desc(buf, record->xl_info, rdata->data);
|
|
}
|
|
elog(LOG, "%s", buf);
|
|
}
|
|
#endif
|
|
|
|
/* Record begin of record in appropriate places */
|
|
if (!no_tran)
|
|
MyLastRecPtr = RecPtr;
|
|
ProcLastRecPtr = RecPtr;
|
|
Insert->PrevRecord = RecPtr;
|
|
MyXactMadeXLogEntry = true;
|
|
|
|
Insert->currpos += SizeOfXLogRecord;
|
|
freespace -= SizeOfXLogRecord;
|
|
|
|
/*
|
|
* Append the data, including backup blocks if any
|
|
*/
|
|
while (write_len)
|
|
{
|
|
while (rdata->data == NULL)
|
|
rdata = rdata->next;
|
|
|
|
if (freespace > 0)
|
|
{
|
|
if (rdata->len > freespace)
|
|
{
|
|
memcpy(Insert->currpos, rdata->data, freespace);
|
|
rdata->data += freespace;
|
|
rdata->len -= freespace;
|
|
write_len -= freespace;
|
|
}
|
|
else
|
|
{
|
|
memcpy(Insert->currpos, rdata->data, rdata->len);
|
|
freespace -= rdata->len;
|
|
write_len -= rdata->len;
|
|
Insert->currpos += rdata->len;
|
|
rdata = rdata->next;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/* Use next buffer */
|
|
updrqst = AdvanceXLInsertBuffer();
|
|
curridx = Insert->curridx;
|
|
/* Insert cont-record header */
|
|
Insert->currpage->xlp_info |= XLP_FIRST_IS_CONTRECORD;
|
|
contrecord = (XLogContRecord *) Insert->currpos;
|
|
contrecord->xl_rem_len = write_len;
|
|
Insert->currpos += SizeOfXLogContRecord;
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
}
|
|
|
|
/* Ensure next record will be properly aligned */
|
|
Insert->currpos = (char *) Insert->currpage +
|
|
MAXALIGN(Insert->currpos - (char *) Insert->currpage);
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
|
|
/*
|
|
* The recptr I return is the beginning of the *next* record. This
|
|
* will be stored as LSN for changed data pages...
|
|
*/
|
|
INSERT_RECPTR(RecPtr, Insert, curridx);
|
|
|
|
/* Need to update shared LogwrtRqst if some block was filled up */
|
|
if (freespace < SizeOfXLogRecord)
|
|
updrqst = true; /* curridx is filled and available for
|
|
* writing out */
|
|
else
|
|
curridx = PrevBufIdx(curridx);
|
|
WriteRqst = XLogCtl->xlblocks[curridx];
|
|
|
|
LWLockRelease(WALInsertLock);
|
|
|
|
if (updrqst)
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
/* advance global request to include new block(s) */
|
|
if (XLByteLT(xlogctl->LogwrtRqst.Write, WriteRqst))
|
|
xlogctl->LogwrtRqst.Write = WriteRqst;
|
|
/* update local result copy while I have the chance */
|
|
LogwrtResult = xlogctl->LogwrtResult;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
}
|
|
|
|
ProcLastRecEnd = RecPtr;
|
|
|
|
END_CRIT_SECTION();
|
|
|
|
return (RecPtr);
|
|
}
|
|
|
|
/*
|
|
* XLogArchiveNotify
|
|
*
|
|
* Create an archive notification file
|
|
*
|
|
* The name of the notification file is the message that will be picked up
|
|
* by the archiver, e.g. we write 0000000100000001000000C6.ready
|
|
* and the archiver then knows to archive XLogDir/0000000100000001000000C6,
|
|
* then when complete, rename it to 0000000100000001000000C6.done
|
|
*/
|
|
static void
|
|
XLogArchiveNotify(const char *xlog)
|
|
{
|
|
char archiveStatusPath[MAXPGPATH];
|
|
FILE *fd;
|
|
|
|
/* insert an otherwise empty file called <XLOG>.ready */
|
|
StatusFilePath(archiveStatusPath, xlog, ".ready");
|
|
fd = AllocateFile(archiveStatusPath, "w");
|
|
if (fd == NULL)
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create archive status file \"%s\": %m",
|
|
archiveStatusPath)));
|
|
return;
|
|
}
|
|
if (FreeFile(fd))
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write archive status file \"%s\": %m",
|
|
archiveStatusPath)));
|
|
return;
|
|
}
|
|
|
|
/* Notify archiver that it's got something to do */
|
|
if (IsUnderPostmaster)
|
|
SendPostmasterSignal(PMSIGNAL_WAKEN_ARCHIVER);
|
|
}
|
|
|
|
/*
|
|
* Convenience routine to notify using log/seg representation of filename
|
|
*/
|
|
static void
|
|
XLogArchiveNotifySeg(uint32 log, uint32 seg)
|
|
{
|
|
char xlog[MAXFNAMELEN];
|
|
|
|
XLogFileName(xlog, ThisTimeLineID, log, seg);
|
|
XLogArchiveNotify(xlog);
|
|
}
|
|
|
|
/*
|
|
* XLogArchiveIsDone
|
|
*
|
|
* Checks for a ".done" archive notification file. This is called when we
|
|
* are ready to delete or recycle an old XLOG segment file. If it is okay
|
|
* to delete it then return true.
|
|
*
|
|
* If <XLOG>.done exists, then return true; else if <XLOG>.ready exists,
|
|
* then return false; else create <XLOG>.ready and return false. The
|
|
* last case covers the possibility that the original attempt to create
|
|
* <XLOG>.ready failed.
|
|
*/
|
|
static bool
|
|
XLogArchiveIsDone(const char *xlog)
|
|
{
|
|
char archiveStatusPath[MAXPGPATH];
|
|
struct stat stat_buf;
|
|
|
|
/* First check for .done --- this is the expected case */
|
|
StatusFilePath(archiveStatusPath, xlog, ".done");
|
|
if (stat(archiveStatusPath, &stat_buf) == 0)
|
|
return true;
|
|
|
|
/* check for .ready --- this means archiver is still busy with it */
|
|
StatusFilePath(archiveStatusPath, xlog, ".ready");
|
|
if (stat(archiveStatusPath, &stat_buf) == 0)
|
|
return false;
|
|
|
|
/* Race condition --- maybe archiver just finished, so recheck */
|
|
StatusFilePath(archiveStatusPath, xlog, ".done");
|
|
if (stat(archiveStatusPath, &stat_buf) == 0)
|
|
return true;
|
|
|
|
/* Retry creation of the .ready file */
|
|
XLogArchiveNotify(xlog);
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* XLogArchiveCleanup
|
|
*
|
|
* Cleanup archive notification file(s) for a particular xlog segment
|
|
*/
|
|
static void
|
|
XLogArchiveCleanup(const char *xlog)
|
|
{
|
|
char archiveStatusPath[MAXPGPATH];
|
|
|
|
/* Remove the .done file */
|
|
StatusFilePath(archiveStatusPath, xlog, ".done");
|
|
unlink(archiveStatusPath);
|
|
/* should we complain about failure? */
|
|
|
|
/* Remove the .ready file if present --- normally it shouldn't be */
|
|
StatusFilePath(archiveStatusPath, xlog, ".ready");
|
|
unlink(archiveStatusPath);
|
|
/* should we complain about failure? */
|
|
}
|
|
|
|
/*
|
|
* Advance the Insert state to the next buffer page, writing out the next
|
|
* buffer if it still contains unwritten data.
|
|
*
|
|
* The global LogwrtRqst.Write pointer needs to be advanced to include the
|
|
* just-filled page. If we can do this for free (without an extra lock),
|
|
* we do so here. Otherwise the caller must do it. We return TRUE if the
|
|
* request update still needs to be done, FALSE if we did it internally.
|
|
*
|
|
* Must be called with WALInsertLock held.
|
|
*/
|
|
static bool
|
|
AdvanceXLInsertBuffer(void)
|
|
{
|
|
XLogCtlInsert *Insert = &XLogCtl->Insert;
|
|
XLogCtlWrite *Write = &XLogCtl->Write;
|
|
uint16 nextidx = NextBufIdx(Insert->curridx);
|
|
bool update_needed = true;
|
|
XLogRecPtr OldPageRqstPtr;
|
|
XLogwrtRqst WriteRqst;
|
|
XLogRecPtr NewPageEndPtr;
|
|
XLogPageHeader NewPage;
|
|
|
|
/* Use Insert->LogwrtResult copy if it's more fresh */
|
|
if (XLByteLT(LogwrtResult.Write, Insert->LogwrtResult.Write))
|
|
LogwrtResult = Insert->LogwrtResult;
|
|
|
|
/*
|
|
* Get ending-offset of the buffer page we need to replace (this may
|
|
* be zero if the buffer hasn't been used yet). Fall through if it's
|
|
* already written out.
|
|
*/
|
|
OldPageRqstPtr = XLogCtl->xlblocks[nextidx];
|
|
if (!XLByteLE(OldPageRqstPtr, LogwrtResult.Write))
|
|
{
|
|
/* nope, got work to do... */
|
|
XLogRecPtr FinishedPageRqstPtr;
|
|
|
|
FinishedPageRqstPtr = XLogCtl->xlblocks[Insert->curridx];
|
|
|
|
/* Before waiting, get info_lck and update LogwrtResult */
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
if (XLByteLT(xlogctl->LogwrtRqst.Write, FinishedPageRqstPtr))
|
|
xlogctl->LogwrtRqst.Write = FinishedPageRqstPtr;
|
|
LogwrtResult = xlogctl->LogwrtResult;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
}
|
|
|
|
update_needed = false; /* Did the shared-request update */
|
|
|
|
if (XLByteLE(OldPageRqstPtr, LogwrtResult.Write))
|
|
{
|
|
/* OK, someone wrote it already */
|
|
Insert->LogwrtResult = LogwrtResult;
|
|
}
|
|
else
|
|
{
|
|
/* Must acquire write lock */
|
|
LWLockAcquire(WALWriteLock, LW_EXCLUSIVE);
|
|
LogwrtResult = Write->LogwrtResult;
|
|
if (XLByteLE(OldPageRqstPtr, LogwrtResult.Write))
|
|
{
|
|
/* OK, someone wrote it already */
|
|
LWLockRelease(WALWriteLock);
|
|
Insert->LogwrtResult = LogwrtResult;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Have to write buffers while holding insert lock. This
|
|
* is not good, so only write as much as we absolutely
|
|
* must.
|
|
*/
|
|
WriteRqst.Write = OldPageRqstPtr;
|
|
WriteRqst.Flush.xlogid = 0;
|
|
WriteRqst.Flush.xrecoff = 0;
|
|
XLogWrite(WriteRqst);
|
|
LWLockRelease(WALWriteLock);
|
|
Insert->LogwrtResult = LogwrtResult;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Now the next buffer slot is free and we can set it up to be the
|
|
* next output page.
|
|
*/
|
|
NewPageEndPtr = XLogCtl->xlblocks[Insert->curridx];
|
|
if (NewPageEndPtr.xrecoff >= XLogFileSize)
|
|
{
|
|
/* crossing a logid boundary */
|
|
NewPageEndPtr.xlogid += 1;
|
|
NewPageEndPtr.xrecoff = BLCKSZ;
|
|
}
|
|
else
|
|
NewPageEndPtr.xrecoff += BLCKSZ;
|
|
XLogCtl->xlblocks[nextidx] = NewPageEndPtr;
|
|
NewPage = (XLogPageHeader) (XLogCtl->pages + nextidx * BLCKSZ);
|
|
Insert->curridx = nextidx;
|
|
Insert->currpage = NewPage;
|
|
Insert->currpos = ((char *) NewPage) + SizeOfXLogShortPHD;
|
|
|
|
/*
|
|
* Be sure to re-zero the buffer so that bytes beyond what we've
|
|
* written will look like zeroes and not valid XLOG records...
|
|
*/
|
|
MemSet((char *) NewPage, 0, BLCKSZ);
|
|
|
|
/*
|
|
* Fill the new page's header
|
|
*/
|
|
NewPage->xlp_magic = XLOG_PAGE_MAGIC;
|
|
/* NewPage->xlp_info = 0; */ /* done by memset */
|
|
NewPage->xlp_tli = ThisTimeLineID;
|
|
NewPage->xlp_pageaddr.xlogid = NewPageEndPtr.xlogid;
|
|
NewPage->xlp_pageaddr.xrecoff = NewPageEndPtr.xrecoff - BLCKSZ;
|
|
|
|
/*
|
|
* If first page of an XLOG segment file, make it a long header.
|
|
*/
|
|
if ((NewPage->xlp_pageaddr.xrecoff % XLogSegSize) == 0)
|
|
{
|
|
XLogLongPageHeader NewLongPage = (XLogLongPageHeader) NewPage;
|
|
|
|
NewLongPage->xlp_sysid = ControlFile->system_identifier;
|
|
NewLongPage->xlp_seg_size = XLogSegSize;
|
|
NewPage->xlp_info |= XLP_LONG_HEADER;
|
|
Insert->currpos = ((char *) NewPage) + SizeOfXLogLongPHD;
|
|
}
|
|
|
|
return update_needed;
|
|
}
|
|
|
|
/*
|
|
* Write and/or fsync the log at least as far as WriteRqst indicates.
|
|
*
|
|
* Must be called with WALWriteLock held.
|
|
*/
|
|
static void
|
|
XLogWrite(XLogwrtRqst WriteRqst)
|
|
{
|
|
XLogCtlWrite *Write = &XLogCtl->Write;
|
|
char *from;
|
|
bool ispartialpage;
|
|
bool use_existent;
|
|
|
|
/*
|
|
* Update local LogwrtResult (caller probably did this already,
|
|
* but...)
|
|
*/
|
|
LogwrtResult = Write->LogwrtResult;
|
|
|
|
while (XLByteLT(LogwrtResult.Write, WriteRqst.Write))
|
|
{
|
|
/*
|
|
* Make sure we're not ahead of the insert process. This could
|
|
* happen if we're passed a bogus WriteRqst.Write that is past the
|
|
* end of the last page that's been initialized by
|
|
* AdvanceXLInsertBuffer.
|
|
*/
|
|
if (!XLByteLT(LogwrtResult.Write, XLogCtl->xlblocks[Write->curridx]))
|
|
elog(PANIC, "xlog write request %X/%X is past end of log %X/%X",
|
|
LogwrtResult.Write.xlogid, LogwrtResult.Write.xrecoff,
|
|
XLogCtl->xlblocks[Write->curridx].xlogid,
|
|
XLogCtl->xlblocks[Write->curridx].xrecoff);
|
|
|
|
/* Advance LogwrtResult.Write to end of current buffer page */
|
|
LogwrtResult.Write = XLogCtl->xlblocks[Write->curridx];
|
|
ispartialpage = XLByteLT(WriteRqst.Write, LogwrtResult.Write);
|
|
|
|
if (!XLByteInPrevSeg(LogwrtResult.Write, openLogId, openLogSeg))
|
|
{
|
|
/*
|
|
* Switch to new logfile segment.
|
|
*/
|
|
if (openLogFile >= 0)
|
|
{
|
|
if (close(openLogFile))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close log file %u, segment %u: %m",
|
|
openLogId, openLogSeg)));
|
|
openLogFile = -1;
|
|
}
|
|
XLByteToPrevSeg(LogwrtResult.Write, openLogId, openLogSeg);
|
|
|
|
/* create/use new log file */
|
|
use_existent = true;
|
|
openLogFile = XLogFileInit(openLogId, openLogSeg,
|
|
&use_existent, true);
|
|
openLogOff = 0;
|
|
|
|
/* update pg_control, unless someone else already did */
|
|
LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
|
|
if (ControlFile->logId < openLogId ||
|
|
(ControlFile->logId == openLogId &&
|
|
ControlFile->logSeg < openLogSeg + 1))
|
|
{
|
|
ControlFile->logId = openLogId;
|
|
ControlFile->logSeg = openLogSeg + 1;
|
|
ControlFile->time = time(NULL);
|
|
UpdateControlFile();
|
|
|
|
/*
|
|
* Signal postmaster to start a checkpoint if it's been
|
|
* too long since the last one. (We look at local copy of
|
|
* RedoRecPtr which might be a little out of date, but
|
|
* should be close enough for this purpose.)
|
|
*/
|
|
if (IsUnderPostmaster &&
|
|
(openLogId != RedoRecPtr.xlogid ||
|
|
openLogSeg >= (RedoRecPtr.xrecoff / XLogSegSize) +
|
|
(uint32) CheckPointSegments))
|
|
{
|
|
#ifdef WAL_DEBUG
|
|
if (XLOG_DEBUG)
|
|
elog(LOG, "time for a checkpoint, signaling bgwriter");
|
|
#endif
|
|
RequestCheckpoint(false);
|
|
}
|
|
}
|
|
LWLockRelease(ControlFileLock);
|
|
}
|
|
|
|
if (openLogFile < 0)
|
|
{
|
|
XLByteToPrevSeg(LogwrtResult.Write, openLogId, openLogSeg);
|
|
openLogFile = XLogFileOpen(openLogId, openLogSeg);
|
|
openLogOff = 0;
|
|
}
|
|
|
|
/* Need to seek in the file? */
|
|
if (openLogOff != (LogwrtResult.Write.xrecoff - BLCKSZ) % XLogSegSize)
|
|
{
|
|
openLogOff = (LogwrtResult.Write.xrecoff - BLCKSZ) % XLogSegSize;
|
|
if (lseek(openLogFile, (off_t) openLogOff, SEEK_SET) < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not seek in log file %u, segment %u to offset %u: %m",
|
|
openLogId, openLogSeg, openLogOff)));
|
|
}
|
|
|
|
/* OK to write the page */
|
|
from = XLogCtl->pages + Write->curridx * BLCKSZ;
|
|
errno = 0;
|
|
if (write(openLogFile, from, BLCKSZ) != BLCKSZ)
|
|
{
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
if (errno == 0)
|
|
errno = ENOSPC;
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to log file %u, segment %u at offset %u: %m",
|
|
openLogId, openLogSeg, openLogOff)));
|
|
}
|
|
openLogOff += BLCKSZ;
|
|
|
|
/*
|
|
* If we just wrote the whole last page of a logfile segment,
|
|
* fsync the segment immediately. This avoids having to go back
|
|
* and re-open prior segments when an fsync request comes along
|
|
* later. Doing it here ensures that one and only one backend will
|
|
* perform this fsync.
|
|
*
|
|
* This is also the right place to notify the Archiver that the
|
|
* segment is ready to copy to archival storage.
|
|
*/
|
|
if (openLogOff >= XLogSegSize && !ispartialpage)
|
|
{
|
|
issue_xlog_fsync();
|
|
LogwrtResult.Flush = LogwrtResult.Write; /* end of current page */
|
|
|
|
if (XLogArchivingActive())
|
|
XLogArchiveNotifySeg(openLogId, openLogSeg);
|
|
}
|
|
|
|
if (ispartialpage)
|
|
{
|
|
/* Only asked to write a partial page */
|
|
LogwrtResult.Write = WriteRqst.Write;
|
|
break;
|
|
}
|
|
Write->curridx = NextBufIdx(Write->curridx);
|
|
}
|
|
|
|
/*
|
|
* If asked to flush, do so
|
|
*/
|
|
if (XLByteLT(LogwrtResult.Flush, WriteRqst.Flush) &&
|
|
XLByteLT(LogwrtResult.Flush, LogwrtResult.Write))
|
|
{
|
|
/*
|
|
* Could get here without iterating above loop, in which case we
|
|
* might have no open file or the wrong one. However, we do not
|
|
* need to fsync more than one file.
|
|
*/
|
|
if (sync_method != SYNC_METHOD_OPEN)
|
|
{
|
|
if (openLogFile >= 0 &&
|
|
!XLByteInPrevSeg(LogwrtResult.Write, openLogId, openLogSeg))
|
|
{
|
|
if (close(openLogFile))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close log file %u, segment %u: %m",
|
|
openLogId, openLogSeg)));
|
|
openLogFile = -1;
|
|
}
|
|
if (openLogFile < 0)
|
|
{
|
|
XLByteToPrevSeg(LogwrtResult.Write, openLogId, openLogSeg);
|
|
openLogFile = XLogFileOpen(openLogId, openLogSeg);
|
|
openLogOff = 0;
|
|
}
|
|
issue_xlog_fsync();
|
|
}
|
|
LogwrtResult.Flush = LogwrtResult.Write;
|
|
}
|
|
|
|
/*
|
|
* Update shared-memory status
|
|
*
|
|
* We make sure that the shared 'request' values do not fall behind the
|
|
* 'result' values. This is not absolutely essential, but it saves
|
|
* some code in a couple of places.
|
|
*/
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
xlogctl->LogwrtResult = LogwrtResult;
|
|
if (XLByteLT(xlogctl->LogwrtRqst.Write, LogwrtResult.Write))
|
|
xlogctl->LogwrtRqst.Write = LogwrtResult.Write;
|
|
if (XLByteLT(xlogctl->LogwrtRqst.Flush, LogwrtResult.Flush))
|
|
xlogctl->LogwrtRqst.Flush = LogwrtResult.Flush;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
}
|
|
|
|
Write->LogwrtResult = LogwrtResult;
|
|
}
|
|
|
|
/*
|
|
* Ensure that all XLOG data through the given position is flushed to disk.
|
|
*
|
|
* NOTE: this differs from XLogWrite mainly in that the WALWriteLock is not
|
|
* already held, and we try to avoid acquiring it if possible.
|
|
*/
|
|
void
|
|
XLogFlush(XLogRecPtr record)
|
|
{
|
|
XLogRecPtr WriteRqstPtr;
|
|
XLogwrtRqst WriteRqst;
|
|
|
|
/* Disabled during REDO */
|
|
if (InRedo)
|
|
return;
|
|
|
|
/* Quick exit if already known flushed */
|
|
if (XLByteLE(record, LogwrtResult.Flush))
|
|
return;
|
|
|
|
#ifdef WAL_DEBUG
|
|
if (XLOG_DEBUG)
|
|
elog(LOG, "xlog flush request %X/%X; write %X/%X; flush %X/%X",
|
|
record.xlogid, record.xrecoff,
|
|
LogwrtResult.Write.xlogid, LogwrtResult.Write.xrecoff,
|
|
LogwrtResult.Flush.xlogid, LogwrtResult.Flush.xrecoff);
|
|
#endif
|
|
|
|
START_CRIT_SECTION();
|
|
|
|
/*
|
|
* Since fsync is usually a horribly expensive operation, we try to
|
|
* piggyback as much data as we can on each fsync: if we see any more
|
|
* data entered into the xlog buffer, we'll write and fsync that too,
|
|
* so that the final value of LogwrtResult.Flush is as large as
|
|
* possible. This gives us some chance of avoiding another fsync
|
|
* immediately after.
|
|
*/
|
|
|
|
/* initialize to given target; may increase below */
|
|
WriteRqstPtr = record;
|
|
|
|
/* read LogwrtResult and update local state */
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
if (XLByteLT(WriteRqstPtr, xlogctl->LogwrtRqst.Write))
|
|
WriteRqstPtr = xlogctl->LogwrtRqst.Write;
|
|
LogwrtResult = xlogctl->LogwrtResult;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
}
|
|
|
|
/* done already? */
|
|
if (!XLByteLE(record, LogwrtResult.Flush))
|
|
{
|
|
/* now wait for the write lock */
|
|
LWLockAcquire(WALWriteLock, LW_EXCLUSIVE);
|
|
LogwrtResult = XLogCtl->Write.LogwrtResult;
|
|
if (!XLByteLE(record, LogwrtResult.Flush))
|
|
{
|
|
/* try to write/flush later additions to XLOG as well */
|
|
if (LWLockConditionalAcquire(WALInsertLock, LW_EXCLUSIVE))
|
|
{
|
|
XLogCtlInsert *Insert = &XLogCtl->Insert;
|
|
uint32 freespace = INSERT_FREESPACE(Insert);
|
|
|
|
if (freespace < SizeOfXLogRecord) /* buffer is full */
|
|
WriteRqstPtr = XLogCtl->xlblocks[Insert->curridx];
|
|
else
|
|
{
|
|
WriteRqstPtr = XLogCtl->xlblocks[Insert->curridx];
|
|
WriteRqstPtr.xrecoff -= freespace;
|
|
}
|
|
LWLockRelease(WALInsertLock);
|
|
WriteRqst.Write = WriteRqstPtr;
|
|
WriteRqst.Flush = WriteRqstPtr;
|
|
}
|
|
else
|
|
{
|
|
WriteRqst.Write = WriteRqstPtr;
|
|
WriteRqst.Flush = record;
|
|
}
|
|
XLogWrite(WriteRqst);
|
|
}
|
|
LWLockRelease(WALWriteLock);
|
|
}
|
|
|
|
END_CRIT_SECTION();
|
|
|
|
/*
|
|
* If we still haven't flushed to the request point then we have a
|
|
* problem; most likely, the requested flush point is past end of
|
|
* XLOG. This has been seen to occur when a disk page has a corrupted
|
|
* LSN.
|
|
*
|
|
* Formerly we treated this as a PANIC condition, but that hurts the
|
|
* system's robustness rather than helping it: we do not want to take
|
|
* down the whole system due to corruption on one data page. In
|
|
* particular, if the bad page is encountered again during recovery
|
|
* then we would be unable to restart the database at all! (This
|
|
* scenario has actually happened in the field several times with 7.1
|
|
* releases. Note that we cannot get here while InRedo is true, but if
|
|
* the bad page is brought in and marked dirty during recovery then
|
|
* CreateCheckPoint will try to flush it at the end of recovery.)
|
|
*
|
|
* The current approach is to ERROR under normal conditions, but only
|
|
* WARNING during recovery, so that the system can be brought up even
|
|
* if there's a corrupt LSN. Note that for calls from xact.c, the
|
|
* ERROR will be promoted to PANIC since xact.c calls this routine
|
|
* inside a critical section. However, calls from bufmgr.c are not
|
|
* within critical sections and so we will not force a restart for a
|
|
* bad LSN on a data page.
|
|
*/
|
|
if (XLByteLT(LogwrtResult.Flush, record))
|
|
elog(InRecovery ? WARNING : ERROR,
|
|
"xlog flush request %X/%X is not satisfied --- flushed only to %X/%X",
|
|
record.xlogid, record.xrecoff,
|
|
LogwrtResult.Flush.xlogid, LogwrtResult.Flush.xrecoff);
|
|
}
|
|
|
|
/*
|
|
* Create a new XLOG file segment, or open a pre-existing one.
|
|
*
|
|
* log, seg: identify segment to be created/opened.
|
|
*
|
|
* *use_existent: if TRUE, OK to use a pre-existing file (else, any
|
|
* pre-existing file will be deleted). On return, TRUE if a pre-existing
|
|
* file was used.
|
|
*
|
|
* use_lock: if TRUE, acquire ControlFileLock while moving file into
|
|
* place. This should be TRUE except during bootstrap log creation. The
|
|
* caller must *not* hold the lock at call.
|
|
*
|
|
* Returns FD of opened file.
|
|
*/
|
|
static int
|
|
XLogFileInit(uint32 log, uint32 seg,
|
|
bool *use_existent, bool use_lock)
|
|
{
|
|
char path[MAXPGPATH];
|
|
char tmppath[MAXPGPATH];
|
|
char zbuffer[BLCKSZ];
|
|
int fd;
|
|
int nbytes;
|
|
|
|
XLogFilePath(path, ThisTimeLineID, log, seg);
|
|
|
|
/*
|
|
* Try to use existent file (checkpoint maker may have created it
|
|
* already)
|
|
*/
|
|
if (*use_existent)
|
|
{
|
|
fd = BasicOpenFile(path, O_RDWR | PG_BINARY | XLOG_SYNC_BIT,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open file \"%s\" (log file %u, segment %u): %m",
|
|
path, log, seg)));
|
|
}
|
|
else
|
|
return (fd);
|
|
}
|
|
|
|
/*
|
|
* Initialize an empty (all zeroes) segment. NOTE: it is possible
|
|
* that another process is doing the same thing. If so, we will end
|
|
* up pre-creating an extra log segment. That seems OK, and better
|
|
* than holding the lock throughout this lengthy process.
|
|
*/
|
|
snprintf(tmppath, MAXPGPATH, "%s/xlogtemp.%d",
|
|
XLogDir, (int) getpid());
|
|
|
|
unlink(tmppath);
|
|
|
|
/* do not use XLOG_SYNC_BIT here --- want to fsync only at end of fill */
|
|
fd = BasicOpenFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m", tmppath)));
|
|
|
|
/*
|
|
* Zero-fill the file. We have to do this the hard way to ensure that
|
|
* all the file space has really been allocated --- on platforms that
|
|
* allow "holes" in files, just seeking to the end doesn't allocate
|
|
* intermediate space. This way, we know that we have all the space
|
|
* and (after the fsync below) that all the indirect blocks are down
|
|
* on disk. Therefore, fdatasync(2) or O_DSYNC will be sufficient to
|
|
* sync future writes to the log file.
|
|
*/
|
|
MemSet(zbuffer, 0, sizeof(zbuffer));
|
|
for (nbytes = 0; nbytes < XLogSegSize; nbytes += sizeof(zbuffer))
|
|
{
|
|
errno = 0;
|
|
if ((int) write(fd, zbuffer, sizeof(zbuffer)) != (int) sizeof(zbuffer))
|
|
{
|
|
int save_errno = errno;
|
|
|
|
/*
|
|
* If we fail to make the file, delete it to release disk
|
|
* space
|
|
*/
|
|
unlink(tmppath);
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
errno = save_errno ? save_errno : ENOSPC;
|
|
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", tmppath)));
|
|
}
|
|
}
|
|
|
|
if (pg_fsync(fd) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync file \"%s\": %m", tmppath)));
|
|
|
|
if (close(fd))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close file \"%s\": %m", tmppath)));
|
|
|
|
/*
|
|
* Now move the segment into place with its final name.
|
|
*
|
|
* If caller didn't want to use a pre-existing file, get rid of any
|
|
* pre-existing file. Otherwise, cope with possibility that someone
|
|
* else has created the file while we were filling ours: if so, use
|
|
* ours to pre-create a future log segment.
|
|
*/
|
|
if (!InstallXLogFileSegment(log, seg, tmppath,
|
|
*use_existent, XLOGfileslop,
|
|
use_lock))
|
|
{
|
|
/* No need for any more future segments... */
|
|
unlink(tmppath);
|
|
}
|
|
|
|
/* Set flag to tell caller there was no existent file */
|
|
*use_existent = false;
|
|
|
|
/* Now open original target segment (might not be file I just made) */
|
|
fd = BasicOpenFile(path, O_RDWR | PG_BINARY | XLOG_SYNC_BIT,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open file \"%s\" (log file %u, segment %u): %m",
|
|
path, log, seg)));
|
|
|
|
return (fd);
|
|
}
|
|
|
|
/*
|
|
* Create a new XLOG file segment by copying a pre-existing one.
|
|
*
|
|
* log, seg: identify segment to be created.
|
|
*
|
|
* srcTLI, srclog, srcseg: identify segment to be copied (could be from
|
|
* a different timeline)
|
|
*
|
|
* Currently this is only used during recovery, and so there are no locking
|
|
* considerations. But we should be just as tense as XLogFileInit to avoid
|
|
* emplacing a bogus file.
|
|
*/
|
|
static void
|
|
XLogFileCopy(uint32 log, uint32 seg,
|
|
TimeLineID srcTLI, uint32 srclog, uint32 srcseg)
|
|
{
|
|
char path[MAXPGPATH];
|
|
char tmppath[MAXPGPATH];
|
|
char buffer[BLCKSZ];
|
|
int srcfd;
|
|
int fd;
|
|
int nbytes;
|
|
|
|
/*
|
|
* Open the source file
|
|
*/
|
|
XLogFilePath(path, srcTLI, srclog, srcseg);
|
|
srcfd = BasicOpenFile(path, O_RDONLY | PG_BINARY, 0);
|
|
if (srcfd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open file \"%s\": %m", path)));
|
|
|
|
/*
|
|
* Copy into a temp file name.
|
|
*/
|
|
snprintf(tmppath, MAXPGPATH, "%s/xlogtemp.%d",
|
|
XLogDir, (int) getpid());
|
|
|
|
unlink(tmppath);
|
|
|
|
/* do not use XLOG_SYNC_BIT here --- want to fsync only at end of fill */
|
|
fd = BasicOpenFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m", tmppath)));
|
|
|
|
/*
|
|
* Do the data copying.
|
|
*/
|
|
for (nbytes = 0; nbytes < XLogSegSize; nbytes += sizeof(buffer))
|
|
{
|
|
errno = 0;
|
|
if ((int) read(srcfd, buffer, sizeof(buffer)) != (int) sizeof(buffer))
|
|
{
|
|
if (errno != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m", path)));
|
|
else
|
|
ereport(PANIC,
|
|
(errmsg("insufficient data in file \"%s\"", path)));
|
|
}
|
|
errno = 0;
|
|
if ((int) write(fd, buffer, sizeof(buffer)) != (int) sizeof(buffer))
|
|
{
|
|
int save_errno = errno;
|
|
|
|
/*
|
|
* If we fail to make the file, delete it to release disk
|
|
* space
|
|
*/
|
|
unlink(tmppath);
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
errno = save_errno ? save_errno : ENOSPC;
|
|
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", tmppath)));
|
|
}
|
|
}
|
|
|
|
if (pg_fsync(fd) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync file \"%s\": %m", tmppath)));
|
|
|
|
if (close(fd))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close file \"%s\": %m", tmppath)));
|
|
|
|
close(srcfd);
|
|
|
|
/*
|
|
* Now move the segment into place with its final name.
|
|
*/
|
|
if (!InstallXLogFileSegment(log, seg, tmppath, false, 0, false))
|
|
elog(PANIC, "InstallXLogFileSegment should not have failed");
|
|
}
|
|
|
|
/*
|
|
* Install a new XLOG segment file as a current or future log segment.
|
|
*
|
|
* This is used both to install a newly-created segment (which has a temp
|
|
* filename while it's being created) and to recycle an old segment.
|
|
*
|
|
* log, seg: identify segment to install as (or first possible target).
|
|
*
|
|
* tmppath: initial name of file to install. It will be renamed into place.
|
|
*
|
|
* find_free: if TRUE, install the new segment at the first empty log/seg
|
|
* number at or after the passed numbers. If FALSE, install the new segment
|
|
* exactly where specified, deleting any existing segment file there.
|
|
*
|
|
* max_advance: maximum number of log/seg slots to advance past the starting
|
|
* point. Fail if no free slot is found in this range. (Irrelevant if
|
|
* find_free is FALSE.)
|
|
*
|
|
* use_lock: if TRUE, acquire ControlFileLock while moving file into
|
|
* place. This should be TRUE except during bootstrap log creation. The
|
|
* caller must *not* hold the lock at call.
|
|
*
|
|
* Returns TRUE if file installed, FALSE if not installed because of
|
|
* exceeding max_advance limit. (Any other kind of failure causes ereport().)
|
|
*/
|
|
static bool
|
|
InstallXLogFileSegment(uint32 log, uint32 seg, char *tmppath,
|
|
bool find_free, int max_advance,
|
|
bool use_lock)
|
|
{
|
|
char path[MAXPGPATH];
|
|
struct stat stat_buf;
|
|
|
|
XLogFilePath(path, ThisTimeLineID, log, seg);
|
|
|
|
/*
|
|
* We want to be sure that only one process does this at a time.
|
|
*/
|
|
if (use_lock)
|
|
LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
|
|
|
|
if (!find_free)
|
|
{
|
|
/* Force installation: get rid of any pre-existing segment file */
|
|
unlink(path);
|
|
}
|
|
else
|
|
{
|
|
/* Find a free slot to put it in */
|
|
while (stat(path, &stat_buf) == 0)
|
|
{
|
|
if (--max_advance < 0)
|
|
{
|
|
/* Failed to find a free slot within specified range */
|
|
if (use_lock)
|
|
LWLockRelease(ControlFileLock);
|
|
return false;
|
|
}
|
|
NextLogSeg(log, seg);
|
|
XLogFilePath(path, ThisTimeLineID, log, seg);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Prefer link() to rename() here just to be really sure that we don't
|
|
* overwrite an existing logfile. However, there shouldn't be one, so
|
|
* rename() is an acceptable substitute except for the truly paranoid.
|
|
*/
|
|
#if HAVE_WORKING_LINK
|
|
if (link(tmppath, path) < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not link file \"%s\" to \"%s\" (initialization of log file %u, segment %u): %m",
|
|
tmppath, path, log, seg)));
|
|
unlink(tmppath);
|
|
#else
|
|
if (rename(tmppath, path) < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not rename file \"%s\" to \"%s\" (initialization of log file %u, segment %u): %m",
|
|
tmppath, path, log, seg)));
|
|
#endif
|
|
|
|
if (use_lock)
|
|
LWLockRelease(ControlFileLock);
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Open a pre-existing logfile segment for writing.
|
|
*/
|
|
static int
|
|
XLogFileOpen(uint32 log, uint32 seg)
|
|
{
|
|
char path[MAXPGPATH];
|
|
int fd;
|
|
|
|
XLogFilePath(path, ThisTimeLineID, log, seg);
|
|
|
|
fd = BasicOpenFile(path, O_RDWR | PG_BINARY | XLOG_SYNC_BIT,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open file \"%s\" (log file %u, segment %u): %m",
|
|
path, log, seg)));
|
|
|
|
return fd;
|
|
}
|
|
|
|
/*
|
|
* Open a logfile segment for reading (during recovery).
|
|
*/
|
|
static int
|
|
XLogFileRead(uint32 log, uint32 seg, int emode)
|
|
{
|
|
char path[MAXPGPATH];
|
|
char xlogfname[MAXFNAMELEN];
|
|
ListCell *cell;
|
|
int fd;
|
|
|
|
/*
|
|
* Loop looking for a suitable timeline ID: we might need to read any
|
|
* of the timelines listed in expectedTLIs.
|
|
*
|
|
* We expect curFileTLI on entry to be the TLI of the preceding file in
|
|
* sequence, or 0 if there was no predecessor. We do not allow
|
|
* curFileTLI to go backwards; this prevents us from picking up the
|
|
* wrong file when a parent timeline extends to higher segment numbers
|
|
* than the child we want to read.
|
|
*/
|
|
foreach(cell, expectedTLIs)
|
|
{
|
|
TimeLineID tli = (TimeLineID) lfirst_int(cell);
|
|
|
|
if (tli < curFileTLI)
|
|
break; /* don't bother looking at too-old TLIs */
|
|
|
|
if (InArchiveRecovery)
|
|
{
|
|
XLogFileName(xlogfname, tli, log, seg);
|
|
restoredFromArchive = RestoreArchivedFile(path, xlogfname,
|
|
"RECOVERYXLOG",
|
|
XLogSegSize);
|
|
}
|
|
else
|
|
XLogFilePath(path, tli, log, seg);
|
|
|
|
fd = BasicOpenFile(path, O_RDONLY | PG_BINARY, 0);
|
|
if (fd >= 0)
|
|
{
|
|
/* Success! */
|
|
curFileTLI = tli;
|
|
return fd;
|
|
}
|
|
if (errno != ENOENT) /* unexpected failure? */
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open file \"%s\" (log file %u, segment %u): %m",
|
|
path, log, seg)));
|
|
}
|
|
|
|
/* Couldn't find it. For simplicity, complain about front timeline */
|
|
XLogFilePath(path, recoveryTargetTLI, log, seg);
|
|
errno = ENOENT;
|
|
ereport(emode,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open file \"%s\" (log file %u, segment %u): %m",
|
|
path, log, seg)));
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Attempt to retrieve the specified file from off-line archival storage.
|
|
* If successful, fill "path" with its complete path (note that this will be
|
|
* a temp file name that doesn't follow the normal naming convention), and
|
|
* return TRUE.
|
|
*
|
|
* If not successful, fill "path" with the name of the normal on-line file
|
|
* (which may or may not actually exist, but we'll try to use it), and return
|
|
* FALSE.
|
|
*
|
|
* For fixed-size files, the caller may pass the expected size as an
|
|
* additional crosscheck on successful recovery. If the file size is not
|
|
* known, set expectedSize = 0.
|
|
*/
|
|
static bool
|
|
RestoreArchivedFile(char *path, const char *xlogfname,
|
|
const char *recovername, off_t expectedSize)
|
|
{
|
|
char xlogpath[MAXPGPATH];
|
|
char xlogRestoreCmd[MAXPGPATH];
|
|
char *dp;
|
|
char *endp;
|
|
const char *sp;
|
|
int rc;
|
|
struct stat stat_buf;
|
|
|
|
/*
|
|
* When doing archive recovery, we always prefer an archived log file
|
|
* even if a file of the same name exists in XLogDir. The reason is
|
|
* that the file in XLogDir could be an old, un-filled or
|
|
* partly-filled version that was copied and restored as part of
|
|
* backing up $PGDATA.
|
|
*
|
|
* We could try to optimize this slightly by checking the local copy
|
|
* lastchange timestamp against the archived copy, but we have no API
|
|
* to do this, nor can we guarantee that the lastchange timestamp was
|
|
* preserved correctly when we copied to archive. Our aim is
|
|
* robustness, so we elect not to do this.
|
|
*
|
|
* If we cannot obtain the log file from the archive, however, we will
|
|
* try to use the XLogDir file if it exists. This is so that we can
|
|
* make use of log segments that weren't yet transferred to the
|
|
* archive.
|
|
*
|
|
* Notice that we don't actually overwrite any files when we copy back
|
|
* from archive because the recoveryRestoreCommand may inadvertently
|
|
* restore inappropriate xlogs, or they may be corrupt, so we may wish
|
|
* to fallback to the segments remaining in current XLogDir later. The
|
|
* copy-from-archive filename is always the same, ensuring that we
|
|
* don't run out of disk space on long recoveries.
|
|
*/
|
|
snprintf(xlogpath, MAXPGPATH, "%s/%s", XLogDir, recovername);
|
|
|
|
/*
|
|
* Make sure there is no existing file named recovername.
|
|
*/
|
|
if (stat(xlogpath, &stat_buf) != 0)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not stat \"%s\": %m",
|
|
xlogpath)));
|
|
}
|
|
else
|
|
{
|
|
if (unlink(xlogpath) != 0)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not remove file \"%s\": %m",
|
|
xlogpath)));
|
|
}
|
|
|
|
/*
|
|
* construct the command to be executed
|
|
*/
|
|
dp = xlogRestoreCmd;
|
|
endp = xlogRestoreCmd + MAXPGPATH - 1;
|
|
*endp = '\0';
|
|
|
|
for (sp = recoveryRestoreCommand; *sp; sp++)
|
|
{
|
|
if (*sp == '%')
|
|
{
|
|
switch (sp[1])
|
|
{
|
|
case 'p':
|
|
/* %p: full path of target file */
|
|
sp++;
|
|
StrNCpy(dp, xlogpath, endp - dp);
|
|
make_native_path(dp);
|
|
dp += strlen(dp);
|
|
break;
|
|
case 'f':
|
|
/* %f: filename of desired file */
|
|
sp++;
|
|
StrNCpy(dp, xlogfname, endp - dp);
|
|
dp += strlen(dp);
|
|
break;
|
|
case '%':
|
|
/* convert %% to a single % */
|
|
sp++;
|
|
if (dp < endp)
|
|
*dp++ = *sp;
|
|
break;
|
|
default:
|
|
/* otherwise treat the % as not special */
|
|
if (dp < endp)
|
|
*dp++ = *sp;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (dp < endp)
|
|
*dp++ = *sp;
|
|
}
|
|
}
|
|
*dp = '\0';
|
|
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("executing restore command \"%s\"",
|
|
xlogRestoreCmd)));
|
|
|
|
/*
|
|
* Copy xlog from archival storage to XLogDir
|
|
*/
|
|
rc = system(xlogRestoreCmd);
|
|
if (rc == 0)
|
|
{
|
|
/*
|
|
* command apparently succeeded, but let's make sure the file is
|
|
* really there now and has the correct size.
|
|
*
|
|
* XXX I made wrong-size a fatal error to ensure the DBA would notice
|
|
* it, but is that too strong? We could try to plow ahead with a
|
|
* local copy of the file ... but the problem is that there
|
|
* probably isn't one, and we'd incorrectly conclude we've reached
|
|
* the end of WAL and we're done recovering ...
|
|
*/
|
|
if (stat(xlogpath, &stat_buf) == 0)
|
|
{
|
|
if (expectedSize > 0 && stat_buf.st_size != expectedSize)
|
|
ereport(FATAL,
|
|
(errmsg("archive file \"%s\" has wrong size: %lu instead of %lu",
|
|
xlogfname,
|
|
(unsigned long) stat_buf.st_size,
|
|
(unsigned long) expectedSize)));
|
|
else
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("restored log file \"%s\" from archive",
|
|
xlogfname)));
|
|
strcpy(path, xlogpath);
|
|
return true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* stat failed */
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not stat \"%s\": %m",
|
|
xlogpath)));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* remember, we rollforward UNTIL the restore fails so failure here is
|
|
* just part of the process... that makes it difficult to determine
|
|
* whether the restore failed because there isn't an archive to
|
|
* restore, or because the administrator has specified the restore
|
|
* program incorrectly. We have to assume the former.
|
|
*/
|
|
ereport(DEBUG1,
|
|
(errmsg("could not restore \"%s\" from archive: return code %d",
|
|
xlogfname, rc)));
|
|
|
|
/*
|
|
* if an archived file is not available, there might still be a
|
|
* version of this file in XLogDir, so return that as the filename to
|
|
* open.
|
|
*
|
|
* In many recovery scenarios we expect this to fail also, but if so that
|
|
* just means we've reached the end of WAL.
|
|
*/
|
|
snprintf(path, MAXPGPATH, "%s/%s", XLogDir, xlogfname);
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Preallocate log files beyond the specified log endpoint, according to
|
|
* the XLOGfile user parameter.
|
|
*/
|
|
static void
|
|
PreallocXlogFiles(XLogRecPtr endptr)
|
|
{
|
|
uint32 _logId;
|
|
uint32 _logSeg;
|
|
int lf;
|
|
bool use_existent;
|
|
|
|
XLByteToPrevSeg(endptr, _logId, _logSeg);
|
|
if ((endptr.xrecoff - 1) % XLogSegSize >=
|
|
(uint32) (0.75 * XLogSegSize))
|
|
{
|
|
NextLogSeg(_logId, _logSeg);
|
|
use_existent = true;
|
|
lf = XLogFileInit(_logId, _logSeg, &use_existent, true);
|
|
close(lf);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Remove or move offline all log files older or equal to passed log/seg#
|
|
*
|
|
* endptr is current (or recent) end of xlog; this is used to determine
|
|
* whether we want to recycle rather than delete no-longer-wanted log files.
|
|
*/
|
|
static void
|
|
MoveOfflineLogs(uint32 log, uint32 seg, XLogRecPtr endptr)
|
|
{
|
|
uint32 endlogId;
|
|
uint32 endlogSeg;
|
|
DIR *xldir;
|
|
struct dirent *xlde;
|
|
char lastoff[MAXFNAMELEN];
|
|
char path[MAXPGPATH];
|
|
|
|
XLByteToPrevSeg(endptr, endlogId, endlogSeg);
|
|
|
|
xldir = AllocateDir(XLogDir);
|
|
if (xldir == NULL)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open transaction log directory \"%s\": %m",
|
|
XLogDir)));
|
|
|
|
XLogFileName(lastoff, ThisTimeLineID, log, seg);
|
|
|
|
errno = 0;
|
|
while ((xlde = readdir(xldir)) != NULL)
|
|
{
|
|
/*
|
|
* We ignore the timeline part of the XLOG segment identifiers in
|
|
* deciding whether a segment is still needed. This ensures that
|
|
* we won't prematurely remove a segment from a parent timeline.
|
|
* We could probably be a little more proactive about removing
|
|
* segments of non-parent timelines, but that would be a whole lot
|
|
* more complicated.
|
|
*
|
|
* We use the alphanumeric sorting property of the filenames to
|
|
* decide which ones are earlier than the lastoff segment.
|
|
*/
|
|
if (strlen(xlde->d_name) == 24 &&
|
|
strspn(xlde->d_name, "0123456789ABCDEF") == 24 &&
|
|
strcmp(xlde->d_name + 8, lastoff + 8) <= 0)
|
|
{
|
|
bool recycle;
|
|
|
|
if (XLogArchivingActive())
|
|
recycle = XLogArchiveIsDone(xlde->d_name);
|
|
else
|
|
recycle = true;
|
|
|
|
if (recycle)
|
|
{
|
|
snprintf(path, MAXPGPATH, "%s/%s", XLogDir, xlde->d_name);
|
|
|
|
/*
|
|
* Before deleting the file, see if it can be recycled as
|
|
* a future log segment. We allow recycling segments up
|
|
* to XLOGfileslop segments beyond the current XLOG
|
|
* location.
|
|
*/
|
|
if (InstallXLogFileSegment(endlogId, endlogSeg, path,
|
|
true, XLOGfileslop,
|
|
true))
|
|
{
|
|
ereport(DEBUG1,
|
|
(errmsg("recycled transaction log file \"%s\"",
|
|
xlde->d_name)));
|
|
}
|
|
else
|
|
{
|
|
/* No need for any more future segments... */
|
|
ereport(DEBUG1,
|
|
(errmsg("removing transaction log file \"%s\"",
|
|
xlde->d_name)));
|
|
unlink(path);
|
|
}
|
|
|
|
XLogArchiveCleanup(xlde->d_name);
|
|
}
|
|
}
|
|
errno = 0;
|
|
}
|
|
#ifdef WIN32
|
|
|
|
/*
|
|
* This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but
|
|
* not in released version
|
|
*/
|
|
if (GetLastError() == ERROR_NO_MORE_FILES)
|
|
errno = 0;
|
|
#endif
|
|
if (errno)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read transaction log directory \"%s\": %m",
|
|
XLogDir)));
|
|
FreeDir(xldir);
|
|
}
|
|
|
|
/*
|
|
* Restore the backup blocks present in an XLOG record, if any.
|
|
*
|
|
* We assume all of the record has been read into memory at *record.
|
|
*
|
|
* Note: when a backup block is available in XLOG, we restore it
|
|
* unconditionally, even if the page in the database appears newer.
|
|
* This is to protect ourselves against database pages that were partially
|
|
* or incorrectly written during a crash. We assume that the XLOG data
|
|
* must be good because it has passed a CRC check, while the database
|
|
* page might not be. This will force us to replay all subsequent
|
|
* modifications of the page that appear in XLOG, rather than possibly
|
|
* ignoring them as already applied, but that's not a huge drawback.
|
|
*/
|
|
static void
|
|
RestoreBkpBlocks(XLogRecord *record, XLogRecPtr lsn)
|
|
{
|
|
Relation reln;
|
|
Buffer buffer;
|
|
Page page;
|
|
BkpBlock bkpb;
|
|
char *blk;
|
|
int i;
|
|
|
|
blk = (char *) XLogRecGetData(record) + record->xl_len;
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (!(record->xl_info & XLR_SET_BKP_BLOCK(i)))
|
|
continue;
|
|
|
|
memcpy((char *) &bkpb, blk, sizeof(BkpBlock));
|
|
blk += sizeof(BkpBlock);
|
|
|
|
reln = XLogOpenRelation(true, record->xl_rmid, bkpb.node);
|
|
|
|
if (reln)
|
|
{
|
|
buffer = XLogReadBuffer(true, reln, bkpb.block);
|
|
if (BufferIsValid(buffer))
|
|
{
|
|
page = (Page) BufferGetPage(buffer);
|
|
memcpy((char *) page, blk, BLCKSZ);
|
|
PageSetLSN(page, lsn);
|
|
PageSetTLI(page, ThisTimeLineID);
|
|
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
|
|
WriteBuffer(buffer);
|
|
}
|
|
}
|
|
|
|
blk += BLCKSZ;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* CRC-check an XLOG record. We do not believe the contents of an XLOG
|
|
* record (other than to the minimal extent of computing the amount of
|
|
* data to read in) until we've checked the CRCs.
|
|
*
|
|
* We assume all of the record has been read into memory at *record.
|
|
*/
|
|
static bool
|
|
RecordIsValid(XLogRecord *record, XLogRecPtr recptr, int emode)
|
|
{
|
|
crc64 crc;
|
|
crc64 cbuf;
|
|
int i;
|
|
uint32 len = record->xl_len;
|
|
char *blk;
|
|
|
|
/* Check CRC of rmgr data and record header */
|
|
INIT_CRC64(crc);
|
|
COMP_CRC64(crc, XLogRecGetData(record), len);
|
|
COMP_CRC64(crc, (char *) record + sizeof(crc64),
|
|
SizeOfXLogRecord - sizeof(crc64));
|
|
FIN_CRC64(crc);
|
|
|
|
if (!EQ_CRC64(record->xl_crc, crc))
|
|
{
|
|
ereport(emode,
|
|
(errmsg("incorrect resource manager data checksum in record at %X/%X",
|
|
recptr.xlogid, recptr.xrecoff)));
|
|
return (false);
|
|
}
|
|
|
|
/* Check CRCs of backup blocks, if any */
|
|
blk = (char *) XLogRecGetData(record) + len;
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (!(record->xl_info & XLR_SET_BKP_BLOCK(i)))
|
|
continue;
|
|
|
|
INIT_CRC64(crc);
|
|
COMP_CRC64(crc, blk + sizeof(BkpBlock), BLCKSZ);
|
|
COMP_CRC64(crc, blk + sizeof(crc64),
|
|
sizeof(BkpBlock) - sizeof(crc64));
|
|
FIN_CRC64(crc);
|
|
memcpy((char *) &cbuf, blk, sizeof(crc64)); /* don't assume
|
|
* alignment */
|
|
|
|
if (!EQ_CRC64(cbuf, crc))
|
|
{
|
|
ereport(emode,
|
|
(errmsg("incorrect checksum of backup block %d in record at %X/%X",
|
|
i + 1, recptr.xlogid, recptr.xrecoff)));
|
|
return (false);
|
|
}
|
|
blk += sizeof(BkpBlock) + BLCKSZ;
|
|
}
|
|
|
|
return (true);
|
|
}
|
|
|
|
/*
|
|
* Attempt to read an XLOG record.
|
|
*
|
|
* If RecPtr is not NULL, try to read a record at that position. Otherwise
|
|
* try to read a record just after the last one previously read.
|
|
*
|
|
* If no valid record is available, returns NULL, or fails if emode is PANIC.
|
|
* (emode must be either PANIC or LOG.)
|
|
*
|
|
* The record is copied into readRecordBuf, so that on successful return,
|
|
* the returned record pointer always points there.
|
|
*/
|
|
static XLogRecord *
|
|
ReadRecord(XLogRecPtr *RecPtr, int emode)
|
|
{
|
|
XLogRecord *record;
|
|
char *buffer;
|
|
XLogRecPtr tmpRecPtr = EndRecPtr;
|
|
bool randAccess = false;
|
|
uint32 len,
|
|
total_len;
|
|
uint32 targetPageOff;
|
|
uint32 targetRecOff;
|
|
uint32 pageHeaderSize;
|
|
unsigned i;
|
|
|
|
if (readBuf == NULL)
|
|
{
|
|
/*
|
|
* First time through, permanently allocate readBuf. We do it
|
|
* this way, rather than just making a static array, for two
|
|
* reasons: (1) no need to waste the storage in most
|
|
* instantiations of the backend; (2) a static char array isn't
|
|
* guaranteed to have any particular alignment, whereas malloc()
|
|
* will provide MAXALIGN'd storage.
|
|
*/
|
|
readBuf = (char *) malloc(BLCKSZ);
|
|
Assert(readBuf != NULL);
|
|
}
|
|
|
|
if (RecPtr == NULL)
|
|
{
|
|
RecPtr = &tmpRecPtr;
|
|
/* fast case if next record is on same page */
|
|
if (nextRecord != NULL)
|
|
{
|
|
record = nextRecord;
|
|
goto got_record;
|
|
}
|
|
/* align old recptr to next page */
|
|
if (tmpRecPtr.xrecoff % BLCKSZ != 0)
|
|
tmpRecPtr.xrecoff += (BLCKSZ - tmpRecPtr.xrecoff % BLCKSZ);
|
|
if (tmpRecPtr.xrecoff >= XLogFileSize)
|
|
{
|
|
(tmpRecPtr.xlogid)++;
|
|
tmpRecPtr.xrecoff = 0;
|
|
}
|
|
/* We will account for page header size below */
|
|
}
|
|
else
|
|
{
|
|
if (!XRecOffIsValid(RecPtr->xrecoff))
|
|
ereport(PANIC,
|
|
(errmsg("invalid record offset at %X/%X",
|
|
RecPtr->xlogid, RecPtr->xrecoff)));
|
|
|
|
/*
|
|
* Since we are going to a random position in WAL, forget any
|
|
* prior state about what timeline we were in, and allow it to be
|
|
* any timeline in expectedTLIs. We also set a flag to allow
|
|
* curFileTLI to go backwards (but we can't reset that variable
|
|
* right here, since we might not change files at all).
|
|
*/
|
|
lastPageTLI = 0; /* see comment in ValidXLOGHeader */
|
|
randAccess = true; /* allow curFileTLI to go backwards too */
|
|
}
|
|
|
|
if (readFile >= 0 && !XLByteInSeg(*RecPtr, readId, readSeg))
|
|
{
|
|
close(readFile);
|
|
readFile = -1;
|
|
}
|
|
XLByteToSeg(*RecPtr, readId, readSeg);
|
|
if (readFile < 0)
|
|
{
|
|
/* Now it's okay to reset curFileTLI if random fetch */
|
|
if (randAccess)
|
|
curFileTLI = 0;
|
|
|
|
readFile = XLogFileRead(readId, readSeg, emode);
|
|
if (readFile < 0)
|
|
goto next_record_is_invalid;
|
|
readOff = (uint32) (-1); /* force read to occur below */
|
|
}
|
|
|
|
targetPageOff = ((RecPtr->xrecoff % XLogSegSize) / BLCKSZ) * BLCKSZ;
|
|
if (readOff != targetPageOff)
|
|
{
|
|
readOff = targetPageOff;
|
|
if (lseek(readFile, (off_t) readOff, SEEK_SET) < 0)
|
|
{
|
|
ereport(emode,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not seek in log file %u, segment %u to offset %u: %m",
|
|
readId, readSeg, readOff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
if (read(readFile, readBuf, BLCKSZ) != BLCKSZ)
|
|
{
|
|
ereport(emode,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read from log file %u, segment %u at offset %u: %m",
|
|
readId, readSeg, readOff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
if (!ValidXLOGHeader((XLogPageHeader) readBuf, emode))
|
|
goto next_record_is_invalid;
|
|
}
|
|
pageHeaderSize = XLogPageHeaderSize((XLogPageHeader) readBuf);
|
|
targetRecOff = RecPtr->xrecoff % BLCKSZ;
|
|
if (targetRecOff == 0)
|
|
{
|
|
/*
|
|
* Can only get here in the continuing-from-prev-page case,
|
|
* because XRecOffIsValid eliminated the zero-page-offset case
|
|
* otherwise. Need to skip over the new page's header.
|
|
*/
|
|
tmpRecPtr.xrecoff += pageHeaderSize;
|
|
targetRecOff = pageHeaderSize;
|
|
}
|
|
else if (targetRecOff < pageHeaderSize)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("invalid record offset at %X/%X",
|
|
RecPtr->xlogid, RecPtr->xrecoff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
if ((((XLogPageHeader) readBuf)->xlp_info & XLP_FIRST_IS_CONTRECORD) &&
|
|
targetRecOff == pageHeaderSize)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("contrecord is requested by %X/%X",
|
|
RecPtr->xlogid, RecPtr->xrecoff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
record = (XLogRecord *) ((char *) readBuf + RecPtr->xrecoff % BLCKSZ);
|
|
|
|
got_record:;
|
|
|
|
/*
|
|
* Currently, xl_len == 0 must be bad data, but that might not be true
|
|
* forever. See note in XLogInsert.
|
|
*/
|
|
if (record->xl_len == 0)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("record with zero length at %X/%X",
|
|
RecPtr->xlogid, RecPtr->xrecoff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
if (record->xl_rmid > RM_MAX_ID)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("invalid resource manager ID %u at %X/%X",
|
|
record->xl_rmid, RecPtr->xlogid, RecPtr->xrecoff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
|
|
/*
|
|
* Compute total length of record including any appended backup
|
|
* blocks.
|
|
*/
|
|
total_len = SizeOfXLogRecord + record->xl_len;
|
|
for (i = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (!(record->xl_info & XLR_SET_BKP_BLOCK(i)))
|
|
continue;
|
|
total_len += sizeof(BkpBlock) + BLCKSZ;
|
|
}
|
|
|
|
/*
|
|
* Allocate or enlarge readRecordBuf as needed. To avoid useless
|
|
* small increases, round its size to a multiple of BLCKSZ, and make
|
|
* sure it's at least 4*BLCKSZ to start with. (That is enough for all
|
|
* "normal" records, but very large commit or abort records might need
|
|
* more space.)
|
|
*/
|
|
if (total_len > readRecordBufSize)
|
|
{
|
|
uint32 newSize = total_len;
|
|
|
|
newSize += BLCKSZ - (newSize % BLCKSZ);
|
|
newSize = Max(newSize, 4 * BLCKSZ);
|
|
if (readRecordBuf)
|
|
free(readRecordBuf);
|
|
readRecordBuf = (char *) malloc(newSize);
|
|
if (!readRecordBuf)
|
|
{
|
|
readRecordBufSize = 0;
|
|
/* We treat this as a "bogus data" condition */
|
|
ereport(emode,
|
|
(errmsg("record length %u at %X/%X too long",
|
|
total_len, RecPtr->xlogid, RecPtr->xrecoff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
readRecordBufSize = newSize;
|
|
}
|
|
|
|
buffer = readRecordBuf;
|
|
nextRecord = NULL;
|
|
len = BLCKSZ - RecPtr->xrecoff % BLCKSZ;
|
|
if (total_len > len)
|
|
{
|
|
/* Need to reassemble record */
|
|
XLogContRecord *contrecord;
|
|
uint32 gotlen = len;
|
|
|
|
memcpy(buffer, record, len);
|
|
record = (XLogRecord *) buffer;
|
|
buffer += len;
|
|
for (;;)
|
|
{
|
|
readOff += BLCKSZ;
|
|
if (readOff >= XLogSegSize)
|
|
{
|
|
close(readFile);
|
|
readFile = -1;
|
|
NextLogSeg(readId, readSeg);
|
|
readFile = XLogFileRead(readId, readSeg, emode);
|
|
if (readFile < 0)
|
|
goto next_record_is_invalid;
|
|
readOff = 0;
|
|
}
|
|
if (read(readFile, readBuf, BLCKSZ) != BLCKSZ)
|
|
{
|
|
ereport(emode,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read from log file %u, segment %u, offset %u: %m",
|
|
readId, readSeg, readOff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
if (!ValidXLOGHeader((XLogPageHeader) readBuf, emode))
|
|
goto next_record_is_invalid;
|
|
if (!(((XLogPageHeader) readBuf)->xlp_info & XLP_FIRST_IS_CONTRECORD))
|
|
{
|
|
ereport(emode,
|
|
(errmsg("there is no contrecord flag in log file %u, segment %u, offset %u",
|
|
readId, readSeg, readOff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
pageHeaderSize = XLogPageHeaderSize((XLogPageHeader) readBuf);
|
|
contrecord = (XLogContRecord *) ((char *) readBuf + pageHeaderSize);
|
|
if (contrecord->xl_rem_len == 0 ||
|
|
total_len != (contrecord->xl_rem_len + gotlen))
|
|
{
|
|
ereport(emode,
|
|
(errmsg("invalid contrecord length %u in log file %u, segment %u, offset %u",
|
|
contrecord->xl_rem_len,
|
|
readId, readSeg, readOff)));
|
|
goto next_record_is_invalid;
|
|
}
|
|
len = BLCKSZ - pageHeaderSize - SizeOfXLogContRecord;
|
|
if (contrecord->xl_rem_len > len)
|
|
{
|
|
memcpy(buffer, (char *) contrecord + SizeOfXLogContRecord, len);
|
|
gotlen += len;
|
|
buffer += len;
|
|
continue;
|
|
}
|
|
memcpy(buffer, (char *) contrecord + SizeOfXLogContRecord,
|
|
contrecord->xl_rem_len);
|
|
break;
|
|
}
|
|
if (!RecordIsValid(record, *RecPtr, emode))
|
|
goto next_record_is_invalid;
|
|
pageHeaderSize = XLogPageHeaderSize((XLogPageHeader) readBuf);
|
|
if (BLCKSZ - SizeOfXLogRecord >= pageHeaderSize +
|
|
SizeOfXLogContRecord + MAXALIGN(contrecord->xl_rem_len))
|
|
{
|
|
nextRecord = (XLogRecord *) ((char *) contrecord +
|
|
SizeOfXLogContRecord + MAXALIGN(contrecord->xl_rem_len));
|
|
}
|
|
EndRecPtr.xlogid = readId;
|
|
EndRecPtr.xrecoff = readSeg * XLogSegSize + readOff +
|
|
pageHeaderSize + SizeOfXLogContRecord +
|
|
MAXALIGN(contrecord->xl_rem_len);
|
|
ReadRecPtr = *RecPtr;
|
|
return record;
|
|
}
|
|
|
|
/* Record does not cross a page boundary */
|
|
if (!RecordIsValid(record, *RecPtr, emode))
|
|
goto next_record_is_invalid;
|
|
if (BLCKSZ - SizeOfXLogRecord >= RecPtr->xrecoff % BLCKSZ +
|
|
MAXALIGN(total_len))
|
|
nextRecord = (XLogRecord *) ((char *) record + MAXALIGN(total_len));
|
|
EndRecPtr.xlogid = RecPtr->xlogid;
|
|
EndRecPtr.xrecoff = RecPtr->xrecoff + MAXALIGN(total_len);
|
|
ReadRecPtr = *RecPtr;
|
|
memcpy(buffer, record, total_len);
|
|
return (XLogRecord *) buffer;
|
|
|
|
next_record_is_invalid:;
|
|
close(readFile);
|
|
readFile = -1;
|
|
nextRecord = NULL;
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Check whether the xlog header of a page just read in looks valid.
|
|
*
|
|
* This is just a convenience subroutine to avoid duplicated code in
|
|
* ReadRecord. It's not intended for use from anywhere else.
|
|
*/
|
|
static bool
|
|
ValidXLOGHeader(XLogPageHeader hdr, int emode)
|
|
{
|
|
XLogRecPtr recaddr;
|
|
|
|
if (hdr->xlp_magic != XLOG_PAGE_MAGIC)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("invalid magic number %04X in log file %u, segment %u, offset %u",
|
|
hdr->xlp_magic, readId, readSeg, readOff)));
|
|
return false;
|
|
}
|
|
if ((hdr->xlp_info & ~XLP_ALL_FLAGS) != 0)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("invalid info bits %04X in log file %u, segment %u, offset %u",
|
|
hdr->xlp_info, readId, readSeg, readOff)));
|
|
return false;
|
|
}
|
|
if (hdr->xlp_info & XLP_LONG_HEADER)
|
|
{
|
|
XLogLongPageHeader longhdr = (XLogLongPageHeader) hdr;
|
|
|
|
if (longhdr->xlp_sysid != ControlFile->system_identifier)
|
|
{
|
|
char fhdrident_str[32];
|
|
char sysident_str[32];
|
|
|
|
/*
|
|
* Format sysids separately to keep platform-dependent format
|
|
* code out of the translatable message string.
|
|
*/
|
|
snprintf(fhdrident_str, sizeof(fhdrident_str), UINT64_FORMAT,
|
|
longhdr->xlp_sysid);
|
|
snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT,
|
|
ControlFile->system_identifier);
|
|
ereport(emode,
|
|
(errmsg("WAL file is from different system"),
|
|
errdetail("WAL file SYSID is %s, pg_control SYSID is %s",
|
|
fhdrident_str, sysident_str)));
|
|
return false;
|
|
}
|
|
if (longhdr->xlp_seg_size != XLogSegSize)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("WAL file is from different system"),
|
|
errdetail("Incorrect XLOG_SEG_SIZE in page header.")));
|
|
return false;
|
|
}
|
|
}
|
|
recaddr.xlogid = readId;
|
|
recaddr.xrecoff = readSeg * XLogSegSize + readOff;
|
|
if (!XLByteEQ(hdr->xlp_pageaddr, recaddr))
|
|
{
|
|
ereport(emode,
|
|
(errmsg("unexpected pageaddr %X/%X in log file %u, segment %u, offset %u",
|
|
hdr->xlp_pageaddr.xlogid, hdr->xlp_pageaddr.xrecoff,
|
|
readId, readSeg, readOff)));
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Check page TLI is one of the expected values.
|
|
*/
|
|
if (!list_member_int(expectedTLIs, (int) hdr->xlp_tli))
|
|
{
|
|
ereport(emode,
|
|
(errmsg("unexpected timeline ID %u in log file %u, segment %u, offset %u",
|
|
hdr->xlp_tli,
|
|
readId, readSeg, readOff)));
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Since child timelines are always assigned a TLI greater than their
|
|
* immediate parent's TLI, we should never see TLI go backwards across
|
|
* successive pages of a consistent WAL sequence.
|
|
*
|
|
* Of course this check should only be applied when advancing
|
|
* sequentially across pages; therefore ReadRecord resets lastPageTLI
|
|
* to zero when going to a random page.
|
|
*/
|
|
if (hdr->xlp_tli < lastPageTLI)
|
|
{
|
|
ereport(emode,
|
|
(errmsg("out-of-sequence timeline ID %u (after %u) in log file %u, segment %u, offset %u",
|
|
hdr->xlp_tli, lastPageTLI,
|
|
readId, readSeg, readOff)));
|
|
return false;
|
|
}
|
|
lastPageTLI = hdr->xlp_tli;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Try to read a timeline's history file.
|
|
*
|
|
* If successful, return the list of component TLIs (the given TLI followed by
|
|
* its ancestor TLIs). If we can't find the history file, assume that the
|
|
* timeline has no parents, and return a list of just the specified timeline
|
|
* ID.
|
|
*/
|
|
static List *
|
|
readTimeLineHistory(TimeLineID targetTLI)
|
|
{
|
|
List *result;
|
|
char path[MAXPGPATH];
|
|
char histfname[MAXFNAMELEN];
|
|
char fline[MAXPGPATH];
|
|
FILE *fd;
|
|
|
|
if (InArchiveRecovery)
|
|
{
|
|
TLHistoryFileName(histfname, targetTLI);
|
|
RestoreArchivedFile(path, histfname, "RECOVERYHISTORY", 0);
|
|
}
|
|
else
|
|
TLHistoryFilePath(path, targetTLI);
|
|
|
|
fd = AllocateFile(path, "r");
|
|
if (fd == NULL)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open \"%s\": %m", path)));
|
|
/* Not there, so assume no parents */
|
|
return list_make1_int((int) targetTLI);
|
|
}
|
|
|
|
result = NIL;
|
|
|
|
/*
|
|
* Parse the file...
|
|
*/
|
|
while (fgets(fline, MAXPGPATH, fd) != NULL)
|
|
{
|
|
/* skip leading whitespace and check for # comment */
|
|
char *ptr;
|
|
char *endptr;
|
|
TimeLineID tli;
|
|
|
|
for (ptr = fline; *ptr; ptr++)
|
|
{
|
|
if (!isspace((unsigned char) *ptr))
|
|
break;
|
|
}
|
|
if (*ptr == '\0' || *ptr == '#')
|
|
continue;
|
|
|
|
/* expect a numeric timeline ID as first field of line */
|
|
tli = (TimeLineID) strtoul(ptr, &endptr, 0);
|
|
if (endptr == ptr)
|
|
ereport(FATAL,
|
|
(errmsg("syntax error in history file: %s", fline),
|
|
errhint("Expected a numeric timeline ID.")));
|
|
|
|
if (result &&
|
|
tli <= (TimeLineID) linitial_int(result))
|
|
ereport(FATAL,
|
|
(errmsg("invalid data in history file: %s", fline),
|
|
errhint("Timeline IDs must be in increasing sequence.")));
|
|
|
|
/* Build list with newest item first */
|
|
result = lcons_int((int) tli, result);
|
|
|
|
/* we ignore the remainder of each line */
|
|
}
|
|
|
|
FreeFile(fd);
|
|
|
|
if (result &&
|
|
targetTLI <= (TimeLineID) linitial_int(result))
|
|
ereport(FATAL,
|
|
(errmsg("invalid data in history file \"%s\"", path),
|
|
errhint("Timeline IDs must be less than child timeline's ID.")));
|
|
|
|
result = lcons_int((int) targetTLI, result);
|
|
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("history of timeline %u is %s",
|
|
targetTLI, nodeToString(result))));
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Probe whether a timeline history file exists for the given timeline ID
|
|
*/
|
|
static bool
|
|
existsTimeLineHistory(TimeLineID probeTLI)
|
|
{
|
|
char path[MAXPGPATH];
|
|
char histfname[MAXFNAMELEN];
|
|
FILE *fd;
|
|
|
|
if (InArchiveRecovery)
|
|
{
|
|
TLHistoryFileName(histfname, probeTLI);
|
|
RestoreArchivedFile(path, histfname, "RECOVERYHISTORY", 0);
|
|
}
|
|
else
|
|
TLHistoryFilePath(path, probeTLI);
|
|
|
|
fd = AllocateFile(path, "r");
|
|
if (fd != NULL)
|
|
{
|
|
FreeFile(fd);
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open \"%s\": %m", path)));
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Find the newest existing timeline, assuming that startTLI exists.
|
|
*
|
|
* Note: while this is somewhat heuristic, it does positively guarantee
|
|
* that (result + 1) is not a known timeline, and therefore it should
|
|
* be safe to assign that ID to a new timeline.
|
|
*/
|
|
static TimeLineID
|
|
findNewestTimeLine(TimeLineID startTLI)
|
|
{
|
|
TimeLineID newestTLI;
|
|
TimeLineID probeTLI;
|
|
|
|
/*
|
|
* The algorithm is just to probe for the existence of timeline
|
|
* history files. XXX is it useful to allow gaps in the sequence?
|
|
*/
|
|
newestTLI = startTLI;
|
|
|
|
for (probeTLI = startTLI + 1;; probeTLI++)
|
|
{
|
|
if (existsTimeLineHistory(probeTLI))
|
|
{
|
|
newestTLI = probeTLI; /* probeTLI exists */
|
|
}
|
|
else
|
|
{
|
|
/* doesn't exist, assume we're done */
|
|
break;
|
|
}
|
|
}
|
|
|
|
return newestTLI;
|
|
}
|
|
|
|
/*
|
|
* Create a new timeline history file.
|
|
*
|
|
* newTLI: ID of the new timeline
|
|
* parentTLI: ID of its immediate parent
|
|
* endTLI et al: ID of the last used WAL file, for annotation purposes
|
|
*
|
|
* Currently this is only used during recovery, and so there are no locking
|
|
* considerations. But we should be just as tense as XLogFileInit to avoid
|
|
* emplacing a bogus file.
|
|
*/
|
|
static void
|
|
writeTimeLineHistory(TimeLineID newTLI, TimeLineID parentTLI,
|
|
TimeLineID endTLI, uint32 endLogId, uint32 endLogSeg)
|
|
{
|
|
char path[MAXPGPATH];
|
|
char tmppath[MAXPGPATH];
|
|
char histfname[MAXFNAMELEN];
|
|
char xlogfname[MAXFNAMELEN];
|
|
char buffer[BLCKSZ];
|
|
int srcfd;
|
|
int fd;
|
|
int nbytes;
|
|
|
|
Assert(newTLI > parentTLI); /* else bad selection of newTLI */
|
|
|
|
/*
|
|
* Write into a temp file name.
|
|
*/
|
|
snprintf(tmppath, MAXPGPATH, "%s/xlogtemp.%d",
|
|
XLogDir, (int) getpid());
|
|
|
|
unlink(tmppath);
|
|
|
|
/* do not use XLOG_SYNC_BIT here --- want to fsync only at end of fill */
|
|
fd = BasicOpenFile(tmppath, O_RDWR | O_CREAT | O_EXCL,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m", tmppath)));
|
|
|
|
/*
|
|
* If a history file exists for the parent, copy it verbatim
|
|
*/
|
|
if (InArchiveRecovery)
|
|
{
|
|
TLHistoryFileName(histfname, parentTLI);
|
|
RestoreArchivedFile(path, histfname, "RECOVERYHISTORY", 0);
|
|
}
|
|
else
|
|
TLHistoryFilePath(path, parentTLI);
|
|
|
|
srcfd = BasicOpenFile(path, O_RDONLY, 0);
|
|
if (srcfd < 0)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open \"%s\": %m", path)));
|
|
/* Not there, so assume parent has no parents */
|
|
}
|
|
else
|
|
{
|
|
for (;;)
|
|
{
|
|
errno = 0;
|
|
nbytes = (int) read(srcfd, buffer, sizeof(buffer));
|
|
if (nbytes < 0 || errno != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m", path)));
|
|
if (nbytes == 0)
|
|
break;
|
|
errno = 0;
|
|
if ((int) write(fd, buffer, nbytes) != nbytes)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
/*
|
|
* If we fail to make the file, delete it to release disk
|
|
* space
|
|
*/
|
|
unlink(tmppath);
|
|
|
|
/*
|
|
* if write didn't set errno, assume problem is no disk
|
|
* space
|
|
*/
|
|
errno = save_errno ? save_errno : ENOSPC;
|
|
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", tmppath)));
|
|
}
|
|
}
|
|
close(srcfd);
|
|
}
|
|
|
|
/*
|
|
* Append one line with the details of this timeline split.
|
|
*
|
|
* If we did have a parent file, insert an extra newline just in case the
|
|
* parent file failed to end with one.
|
|
*/
|
|
XLogFileName(xlogfname, endTLI, endLogId, endLogSeg);
|
|
|
|
snprintf(buffer, sizeof(buffer),
|
|
"%s%u\t%s\t%s transaction %u at %s\n",
|
|
(srcfd < 0) ? "" : "\n",
|
|
parentTLI,
|
|
xlogfname,
|
|
recoveryStopAfter ? "after" : "before",
|
|
recoveryStopXid,
|
|
str_time(recoveryStopTime));
|
|
|
|
nbytes = strlen(buffer);
|
|
errno = 0;
|
|
if ((int) write(fd, buffer, nbytes) != nbytes)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
/*
|
|
* If we fail to make the file, delete it to release disk space
|
|
*/
|
|
unlink(tmppath);
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
errno = save_errno ? save_errno : ENOSPC;
|
|
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", tmppath)));
|
|
}
|
|
|
|
if (pg_fsync(fd) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync file \"%s\": %m", tmppath)));
|
|
|
|
if (close(fd))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close file \"%s\": %m", tmppath)));
|
|
|
|
|
|
/*
|
|
* Now move the completed history file into place with its final name.
|
|
*/
|
|
TLHistoryFilePath(path, newTLI);
|
|
|
|
/*
|
|
* Prefer link() to rename() here just to be really sure that we don't
|
|
* overwrite an existing logfile. However, there shouldn't be one, so
|
|
* rename() is an acceptable substitute except for the truly paranoid.
|
|
*/
|
|
#if HAVE_WORKING_LINK
|
|
if (link(tmppath, path) < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not link file \"%s\" to \"%s\": %m",
|
|
tmppath, path)));
|
|
unlink(tmppath);
|
|
#else
|
|
if (rename(tmppath, path) < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not rename file \"%s\" to \"%s\": %m",
|
|
tmppath, path)));
|
|
#endif
|
|
|
|
/* The history file can be archived immediately. */
|
|
TLHistoryFileName(histfname, newTLI);
|
|
XLogArchiveNotify(histfname);
|
|
}
|
|
|
|
/*
|
|
* I/O routines for pg_control
|
|
*
|
|
* *ControlFile is a buffer in shared memory that holds an image of the
|
|
* contents of pg_control. WriteControlFile() initializes pg_control
|
|
* given a preloaded buffer, ReadControlFile() loads the buffer from
|
|
* the pg_control file (during postmaster or standalone-backend startup),
|
|
* and UpdateControlFile() rewrites pg_control after we modify xlog state.
|
|
*
|
|
* For simplicity, WriteControlFile() initializes the fields of pg_control
|
|
* that are related to checking backend/database compatibility, and
|
|
* ReadControlFile() verifies they are correct. We could split out the
|
|
* I/O and compatibility-check functions, but there seems no need currently.
|
|
*/
|
|
|
|
void
|
|
XLOGPathInit(void)
|
|
{
|
|
/* Init XLOG file paths */
|
|
snprintf(XLogDir, MAXPGPATH, "%s/pg_xlog", DataDir);
|
|
snprintf(ControlFilePath, MAXPGPATH, "%s/global/pg_control", DataDir);
|
|
}
|
|
|
|
static void
|
|
WriteControlFile(void)
|
|
{
|
|
int fd;
|
|
char buffer[BLCKSZ]; /* need not be aligned */
|
|
char *localeptr;
|
|
|
|
/*
|
|
* Initialize version and compatibility-check fields
|
|
*/
|
|
ControlFile->pg_control_version = PG_CONTROL_VERSION;
|
|
ControlFile->catalog_version_no = CATALOG_VERSION_NO;
|
|
ControlFile->blcksz = BLCKSZ;
|
|
ControlFile->relseg_size = RELSEG_SIZE;
|
|
ControlFile->xlog_seg_size = XLOG_SEG_SIZE;
|
|
|
|
ControlFile->nameDataLen = NAMEDATALEN;
|
|
ControlFile->funcMaxArgs = FUNC_MAX_ARGS;
|
|
|
|
#ifdef HAVE_INT64_TIMESTAMP
|
|
ControlFile->enableIntTimes = TRUE;
|
|
#else
|
|
ControlFile->enableIntTimes = FALSE;
|
|
#endif
|
|
|
|
ControlFile->localeBuflen = LOCALE_NAME_BUFLEN;
|
|
localeptr = setlocale(LC_COLLATE, NULL);
|
|
if (!localeptr)
|
|
ereport(PANIC,
|
|
(errmsg("invalid LC_COLLATE setting")));
|
|
StrNCpy(ControlFile->lc_collate, localeptr, LOCALE_NAME_BUFLEN);
|
|
localeptr = setlocale(LC_CTYPE, NULL);
|
|
if (!localeptr)
|
|
ereport(PANIC,
|
|
(errmsg("invalid LC_CTYPE setting")));
|
|
StrNCpy(ControlFile->lc_ctype, localeptr, LOCALE_NAME_BUFLEN);
|
|
|
|
/* Contents are protected with a CRC */
|
|
INIT_CRC64(ControlFile->crc);
|
|
COMP_CRC64(ControlFile->crc,
|
|
(char *) ControlFile + sizeof(crc64),
|
|
sizeof(ControlFileData) - sizeof(crc64));
|
|
FIN_CRC64(ControlFile->crc);
|
|
|
|
/*
|
|
* We write out BLCKSZ bytes into pg_control, zero-padding the excess
|
|
* over sizeof(ControlFileData). This reduces the odds of
|
|
* premature-EOF errors when reading pg_control. We'll still fail
|
|
* when we check the contents of the file, but hopefully with a more
|
|
* specific error than "couldn't read pg_control".
|
|
*/
|
|
if (sizeof(ControlFileData) > BLCKSZ)
|
|
ereport(PANIC,
|
|
(errmsg("sizeof(ControlFileData) is larger than BLCKSZ; fix either one")));
|
|
|
|
memset(buffer, 0, BLCKSZ);
|
|
memcpy(buffer, ControlFile, sizeof(ControlFileData));
|
|
|
|
fd = BasicOpenFile(ControlFilePath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
|
|
S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create control file \"%s\": %m",
|
|
ControlFilePath)));
|
|
|
|
errno = 0;
|
|
if (write(fd, buffer, BLCKSZ) != BLCKSZ)
|
|
{
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
if (errno == 0)
|
|
errno = ENOSPC;
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to control file: %m")));
|
|
}
|
|
|
|
if (pg_fsync(fd) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync control file: %m")));
|
|
|
|
if (close(fd))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close control file: %m")));
|
|
}
|
|
|
|
static void
|
|
ReadControlFile(void)
|
|
{
|
|
crc64 crc;
|
|
int fd;
|
|
|
|
/*
|
|
* Read data...
|
|
*/
|
|
fd = BasicOpenFile(ControlFilePath, O_RDWR | PG_BINARY, S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open control file \"%s\": %m",
|
|
ControlFilePath)));
|
|
|
|
if (read(fd, ControlFile, sizeof(ControlFileData)) != sizeof(ControlFileData))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read from control file: %m")));
|
|
|
|
close(fd);
|
|
|
|
/*
|
|
* Check for expected pg_control format version. If this is wrong,
|
|
* the CRC check will likely fail because we'll be checking the wrong
|
|
* number of bytes. Complaining about wrong version will probably be
|
|
* more enlightening than complaining about wrong CRC.
|
|
*/
|
|
if (ControlFile->pg_control_version != PG_CONTROL_VERSION)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with PG_CONTROL_VERSION %d,"
|
|
" but the server was compiled with PG_CONTROL_VERSION %d.",
|
|
ControlFile->pg_control_version, PG_CONTROL_VERSION),
|
|
errhint("It looks like you need to initdb.")));
|
|
/* Now check the CRC. */
|
|
INIT_CRC64(crc);
|
|
COMP_CRC64(crc,
|
|
(char *) ControlFile + sizeof(crc64),
|
|
sizeof(ControlFileData) - sizeof(crc64));
|
|
FIN_CRC64(crc);
|
|
|
|
if (!EQ_CRC64(crc, ControlFile->crc))
|
|
ereport(FATAL,
|
|
(errmsg("incorrect checksum in control file")));
|
|
|
|
/*
|
|
* Do compatibility checking immediately. We do this here for 2
|
|
* reasons:
|
|
*
|
|
* (1) if the database isn't compatible with the backend executable, we
|
|
* want to abort before we can possibly do any damage;
|
|
*
|
|
* (2) this code is executed in the postmaster, so the setlocale() will
|
|
* propagate to forked backends, which aren't going to read this file
|
|
* for themselves. (These locale settings are considered critical
|
|
* compatibility items because they can affect sort order of indexes.)
|
|
*/
|
|
if (ControlFile->catalog_version_no != CATALOG_VERSION_NO)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with CATALOG_VERSION_NO %d,"
|
|
" but the server was compiled with CATALOG_VERSION_NO %d.",
|
|
ControlFile->catalog_version_no, CATALOG_VERSION_NO),
|
|
errhint("It looks like you need to initdb.")));
|
|
if (ControlFile->blcksz != BLCKSZ)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with BLCKSZ %d,"
|
|
" but the server was compiled with BLCKSZ %d.",
|
|
ControlFile->blcksz, BLCKSZ),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
if (ControlFile->relseg_size != RELSEG_SIZE)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with RELSEG_SIZE %d,"
|
|
" but the server was compiled with RELSEG_SIZE %d.",
|
|
ControlFile->relseg_size, RELSEG_SIZE),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
if (ControlFile->xlog_seg_size != XLOG_SEG_SIZE)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with XLOG_SEG_SIZE %d,"
|
|
" but the server was compiled with XLOG_SEG_SIZE %d.",
|
|
ControlFile->xlog_seg_size, XLOG_SEG_SIZE),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
if (ControlFile->nameDataLen != NAMEDATALEN)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with NAMEDATALEN %d,"
|
|
" but the server was compiled with NAMEDATALEN %d.",
|
|
ControlFile->nameDataLen, NAMEDATALEN),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
if (ControlFile->funcMaxArgs != FUNC_MAX_ARGS)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with FUNC_MAX_ARGS %d,"
|
|
" but the server was compiled with FUNC_MAX_ARGS %d.",
|
|
ControlFile->funcMaxArgs, FUNC_MAX_ARGS),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
|
|
#ifdef HAVE_INT64_TIMESTAMP
|
|
if (ControlFile->enableIntTimes != TRUE)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized without HAVE_INT64_TIMESTAMP"
|
|
" but the server was compiled with HAVE_INT64_TIMESTAMP."),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
#else
|
|
if (ControlFile->enableIntTimes != FALSE)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with HAVE_INT64_TIMESTAMP"
|
|
" but the server was compiled without HAVE_INT64_TIMESTAMP."),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
#endif
|
|
|
|
if (ControlFile->localeBuflen != LOCALE_NAME_BUFLEN)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with server"),
|
|
errdetail("The database cluster was initialized with LOCALE_NAME_BUFLEN %d,"
|
|
" but the server was compiled with LOCALE_NAME_BUFLEN %d.",
|
|
ControlFile->localeBuflen, LOCALE_NAME_BUFLEN),
|
|
errhint("It looks like you need to recompile or initdb.")));
|
|
if (setlocale(LC_COLLATE, ControlFile->lc_collate) == NULL)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with operating system"),
|
|
errdetail("The database cluster was initialized with LC_COLLATE \"%s\","
|
|
" which is not recognized by setlocale().",
|
|
ControlFile->lc_collate),
|
|
errhint("It looks like you need to initdb or install locale support.")));
|
|
if (setlocale(LC_CTYPE, ControlFile->lc_ctype) == NULL)
|
|
ereport(FATAL,
|
|
(errmsg("database files are incompatible with operating system"),
|
|
errdetail("The database cluster was initialized with LC_CTYPE \"%s\","
|
|
" which is not recognized by setlocale().",
|
|
ControlFile->lc_ctype),
|
|
errhint("It looks like you need to initdb or install locale support.")));
|
|
|
|
/* Make the fixed locale settings visible as GUC variables, too */
|
|
SetConfigOption("lc_collate", ControlFile->lc_collate,
|
|
PGC_INTERNAL, PGC_S_OVERRIDE);
|
|
SetConfigOption("lc_ctype", ControlFile->lc_ctype,
|
|
PGC_INTERNAL, PGC_S_OVERRIDE);
|
|
}
|
|
|
|
void
|
|
UpdateControlFile(void)
|
|
{
|
|
int fd;
|
|
|
|
INIT_CRC64(ControlFile->crc);
|
|
COMP_CRC64(ControlFile->crc,
|
|
(char *) ControlFile + sizeof(crc64),
|
|
sizeof(ControlFileData) - sizeof(crc64));
|
|
FIN_CRC64(ControlFile->crc);
|
|
|
|
fd = BasicOpenFile(ControlFilePath, O_RDWR | PG_BINARY, S_IRUSR | S_IWUSR);
|
|
if (fd < 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open control file \"%s\": %m",
|
|
ControlFilePath)));
|
|
|
|
errno = 0;
|
|
if (write(fd, ControlFile, sizeof(ControlFileData)) != sizeof(ControlFileData))
|
|
{
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
if (errno == 0)
|
|
errno = ENOSPC;
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to control file: %m")));
|
|
}
|
|
|
|
if (pg_fsync(fd) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync control file: %m")));
|
|
|
|
if (close(fd))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close control file: %m")));
|
|
}
|
|
|
|
/*
|
|
* Initialization of shared memory for XLOG
|
|
*/
|
|
|
|
int
|
|
XLOGShmemSize(void)
|
|
{
|
|
if (XLOGbuffers < MinXLOGbuffers)
|
|
XLOGbuffers = MinXLOGbuffers;
|
|
|
|
return MAXALIGN(sizeof(XLogCtlData) + sizeof(XLogRecPtr) * XLOGbuffers)
|
|
+ BLCKSZ * XLOGbuffers +
|
|
MAXALIGN(sizeof(ControlFileData));
|
|
}
|
|
|
|
void
|
|
XLOGShmemInit(void)
|
|
{
|
|
bool foundXLog,
|
|
foundCFile;
|
|
|
|
/* this must agree with space requested by XLOGShmemSize() */
|
|
if (XLOGbuffers < MinXLOGbuffers)
|
|
XLOGbuffers = MinXLOGbuffers;
|
|
|
|
XLogCtl = (XLogCtlData *)
|
|
ShmemInitStruct("XLOG Ctl",
|
|
MAXALIGN(sizeof(XLogCtlData) +
|
|
sizeof(XLogRecPtr) * XLOGbuffers)
|
|
+ BLCKSZ * XLOGbuffers,
|
|
&foundXLog);
|
|
ControlFile = (ControlFileData *)
|
|
ShmemInitStruct("Control File", sizeof(ControlFileData), &foundCFile);
|
|
|
|
if (foundXLog || foundCFile)
|
|
{
|
|
/* both should be present or neither */
|
|
Assert(foundXLog && foundCFile);
|
|
return;
|
|
}
|
|
|
|
memset(XLogCtl, 0, sizeof(XLogCtlData));
|
|
|
|
/*
|
|
* Since XLogCtlData contains XLogRecPtr fields, its sizeof should be
|
|
* a multiple of the alignment for same, so no extra alignment padding
|
|
* is needed here.
|
|
*/
|
|
XLogCtl->xlblocks = (XLogRecPtr *)
|
|
(((char *) XLogCtl) + sizeof(XLogCtlData));
|
|
memset(XLogCtl->xlblocks, 0, sizeof(XLogRecPtr) * XLOGbuffers);
|
|
|
|
/*
|
|
* Here, on the other hand, we must MAXALIGN to ensure the page
|
|
* buffers have worst-case alignment.
|
|
*/
|
|
XLogCtl->pages =
|
|
((char *) XLogCtl) + MAXALIGN(sizeof(XLogCtlData) +
|
|
sizeof(XLogRecPtr) * XLOGbuffers);
|
|
memset(XLogCtl->pages, 0, BLCKSZ * XLOGbuffers);
|
|
|
|
/*
|
|
* Do basic initialization of XLogCtl shared data. (StartupXLOG will
|
|
* fill in additional info.)
|
|
*/
|
|
XLogCtl->XLogCacheByte = BLCKSZ * XLOGbuffers;
|
|
XLogCtl->XLogCacheBlck = XLOGbuffers - 1;
|
|
XLogCtl->Insert.currpage = (XLogPageHeader) (XLogCtl->pages);
|
|
SpinLockInit(&XLogCtl->info_lck);
|
|
|
|
/*
|
|
* If we are not in bootstrap mode, pg_control should already exist.
|
|
* Read and validate it immediately (see comments in ReadControlFile()
|
|
* for the reasons why).
|
|
*/
|
|
if (!IsBootstrapProcessingMode())
|
|
ReadControlFile();
|
|
}
|
|
|
|
/*
|
|
* This func must be called ONCE on system install. It creates pg_control
|
|
* and the initial XLOG segment.
|
|
*/
|
|
void
|
|
BootStrapXLOG(void)
|
|
{
|
|
CheckPoint checkPoint;
|
|
char *buffer;
|
|
XLogPageHeader page;
|
|
XLogLongPageHeader longpage;
|
|
XLogRecord *record;
|
|
bool use_existent;
|
|
uint64 sysidentifier;
|
|
struct timeval tv;
|
|
crc64 crc;
|
|
|
|
/*
|
|
* Select a hopefully-unique system identifier code for this
|
|
* installation. We use the result of gettimeofday(), including the
|
|
* fractional seconds field, as being about as unique as we can easily
|
|
* get. (Think not to use random(), since it hasn't been seeded and
|
|
* there's no portable way to seed it other than the system clock
|
|
* value...) The upper half of the uint64 value is just the tv_sec
|
|
* part, while the lower half is the XOR of tv_sec and tv_usec. This
|
|
* is to ensure that we don't lose uniqueness unnecessarily if
|
|
* "uint64" is really only 32 bits wide. A person knowing this
|
|
* encoding can determine the initialization time of the installation,
|
|
* which could perhaps be useful sometimes.
|
|
*/
|
|
gettimeofday(&tv, NULL);
|
|
sysidentifier = ((uint64) tv.tv_sec) << 32;
|
|
sysidentifier |= (uint32) (tv.tv_sec | tv.tv_usec);
|
|
|
|
/* First timeline ID is always 1 */
|
|
ThisTimeLineID = 1;
|
|
|
|
/* Use malloc() to ensure buffer is MAXALIGNED */
|
|
buffer = (char *) malloc(BLCKSZ);
|
|
page = (XLogPageHeader) buffer;
|
|
memset(buffer, 0, BLCKSZ);
|
|
|
|
/* Set up information for the initial checkpoint record */
|
|
checkPoint.redo.xlogid = 0;
|
|
checkPoint.redo.xrecoff = SizeOfXLogLongPHD;
|
|
checkPoint.undo = checkPoint.redo;
|
|
checkPoint.ThisTimeLineID = ThisTimeLineID;
|
|
checkPoint.nextXid = FirstNormalTransactionId;
|
|
checkPoint.nextOid = BootstrapObjectIdData;
|
|
checkPoint.time = time(NULL);
|
|
|
|
ShmemVariableCache->nextXid = checkPoint.nextXid;
|
|
ShmemVariableCache->nextOid = checkPoint.nextOid;
|
|
ShmemVariableCache->oidCount = 0;
|
|
|
|
/* Set up the XLOG page header */
|
|
page->xlp_magic = XLOG_PAGE_MAGIC;
|
|
page->xlp_info = XLP_LONG_HEADER;
|
|
page->xlp_tli = ThisTimeLineID;
|
|
page->xlp_pageaddr.xlogid = 0;
|
|
page->xlp_pageaddr.xrecoff = 0;
|
|
longpage = (XLogLongPageHeader) page;
|
|
longpage->xlp_sysid = sysidentifier;
|
|
longpage->xlp_seg_size = XLogSegSize;
|
|
|
|
/* Insert the initial checkpoint record */
|
|
record = (XLogRecord *) ((char *) page + SizeOfXLogLongPHD);
|
|
record->xl_prev.xlogid = 0;
|
|
record->xl_prev.xrecoff = 0;
|
|
record->xl_xid = InvalidTransactionId;
|
|
record->xl_len = sizeof(checkPoint);
|
|
record->xl_info = XLOG_CHECKPOINT_SHUTDOWN;
|
|
record->xl_rmid = RM_XLOG_ID;
|
|
memcpy(XLogRecGetData(record), &checkPoint, sizeof(checkPoint));
|
|
|
|
INIT_CRC64(crc);
|
|
COMP_CRC64(crc, &checkPoint, sizeof(checkPoint));
|
|
COMP_CRC64(crc, (char *) record + sizeof(crc64),
|
|
SizeOfXLogRecord - sizeof(crc64));
|
|
FIN_CRC64(crc);
|
|
record->xl_crc = crc;
|
|
|
|
/* Create first XLOG segment file */
|
|
use_existent = false;
|
|
openLogFile = XLogFileInit(0, 0, &use_existent, false);
|
|
|
|
/* Write the first page with the initial record */
|
|
errno = 0;
|
|
if (write(openLogFile, buffer, BLCKSZ) != BLCKSZ)
|
|
{
|
|
/* if write didn't set errno, assume problem is no disk space */
|
|
if (errno == 0)
|
|
errno = ENOSPC;
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write bootstrap transaction log file: %m")));
|
|
}
|
|
|
|
if (pg_fsync(openLogFile) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync bootstrap transaction log file: %m")));
|
|
|
|
if (close(openLogFile))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close bootstrap transaction log file: %m")));
|
|
|
|
openLogFile = -1;
|
|
|
|
/* Now create pg_control */
|
|
|
|
memset(ControlFile, 0, sizeof(ControlFileData));
|
|
/* Initialize pg_control status fields */
|
|
ControlFile->system_identifier = sysidentifier;
|
|
ControlFile->state = DB_SHUTDOWNED;
|
|
ControlFile->time = checkPoint.time;
|
|
ControlFile->logId = 0;
|
|
ControlFile->logSeg = 1;
|
|
ControlFile->checkPoint = checkPoint.redo;
|
|
ControlFile->checkPointCopy = checkPoint;
|
|
/* some additional ControlFile fields are set in WriteControlFile() */
|
|
|
|
WriteControlFile();
|
|
|
|
/* Bootstrap the commit log, too */
|
|
BootStrapCLOG();
|
|
BootStrapSUBTRANS();
|
|
}
|
|
|
|
static char *
|
|
str_time(time_t tnow)
|
|
{
|
|
static char buf[128];
|
|
|
|
strftime(buf, sizeof(buf),
|
|
"%Y-%m-%d %H:%M:%S %Z",
|
|
localtime(&tnow));
|
|
|
|
return buf;
|
|
}
|
|
|
|
/*
|
|
* See if there is a recovery command file (recovery.conf), and if so
|
|
* read in parameters for archive recovery.
|
|
*
|
|
* XXX longer term intention is to expand this to
|
|
* cater for additional parameters and controls
|
|
* possibly use a flex lexer similar to the GUC one
|
|
*/
|
|
static void
|
|
readRecoveryCommandFile(void)
|
|
{
|
|
char recoveryCommandFile[MAXPGPATH];
|
|
FILE *fd;
|
|
char cmdline[MAXPGPATH];
|
|
TimeLineID rtli = 0;
|
|
bool rtliGiven = false;
|
|
bool syntaxError = false;
|
|
|
|
snprintf(recoveryCommandFile, MAXPGPATH, "%s/recovery.conf", DataDir);
|
|
fd = AllocateFile(recoveryCommandFile, "r");
|
|
if (fd == NULL)
|
|
{
|
|
if (errno == ENOENT)
|
|
return; /* not there, so no archive recovery */
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open recovery command file \"%s\": %m",
|
|
recoveryCommandFile)));
|
|
}
|
|
|
|
ereport(LOG,
|
|
(errmsg("starting archive recovery")));
|
|
|
|
/*
|
|
* Parse the file...
|
|
*/
|
|
while (fgets(cmdline, MAXPGPATH, fd) != NULL)
|
|
{
|
|
/* skip leading whitespace and check for # comment */
|
|
char *ptr;
|
|
char *tok1;
|
|
char *tok2;
|
|
|
|
for (ptr = cmdline; *ptr; ptr++)
|
|
{
|
|
if (!isspace((unsigned char) *ptr))
|
|
break;
|
|
}
|
|
if (*ptr == '\0' || *ptr == '#')
|
|
continue;
|
|
|
|
/* identify the quoted parameter value */
|
|
tok1 = strtok(ptr, "'");
|
|
if (!tok1)
|
|
{
|
|
syntaxError = true;
|
|
break;
|
|
}
|
|
tok2 = strtok(NULL, "'");
|
|
if (!tok2)
|
|
{
|
|
syntaxError = true;
|
|
break;
|
|
}
|
|
/* reparse to get just the parameter name */
|
|
tok1 = strtok(ptr, " \t=");
|
|
if (!tok1)
|
|
{
|
|
syntaxError = true;
|
|
break;
|
|
}
|
|
|
|
if (strcmp(tok1, "restore_command") == 0)
|
|
{
|
|
recoveryRestoreCommand = pstrdup(tok2);
|
|
ereport(LOG,
|
|
(errmsg("restore_command = \"%s\"",
|
|
recoveryRestoreCommand)));
|
|
}
|
|
else if (strcmp(tok1, "recovery_target_timeline") == 0)
|
|
{
|
|
rtliGiven = true;
|
|
if (strcmp(tok2, "latest") == 0)
|
|
rtli = 0;
|
|
else
|
|
{
|
|
errno = 0;
|
|
rtli = (TimeLineID) strtoul(tok2, NULL, 0);
|
|
if (errno == EINVAL || errno == ERANGE)
|
|
ereport(FATAL,
|
|
(errmsg("recovery_target_timeline is not a valid number: \"%s\"",
|
|
tok2)));
|
|
}
|
|
if (rtli)
|
|
ereport(LOG,
|
|
(errmsg("recovery_target_timeline = %u", rtli)));
|
|
else
|
|
ereport(LOG,
|
|
(errmsg("recovery_target_timeline = latest")));
|
|
}
|
|
else if (strcmp(tok1, "recovery_target_xid") == 0)
|
|
{
|
|
errno = 0;
|
|
recoveryTargetXid = (TransactionId) strtoul(tok2, NULL, 0);
|
|
if (errno == EINVAL || errno == ERANGE)
|
|
ereport(FATAL,
|
|
(errmsg("recovery_target_xid is not a valid number: \"%s\"",
|
|
tok2)));
|
|
ereport(LOG,
|
|
(errmsg("recovery_target_xid = %u",
|
|
recoveryTargetXid)));
|
|
recoveryTarget = true;
|
|
recoveryTargetExact = true;
|
|
}
|
|
else if (strcmp(tok1, "recovery_target_time") == 0)
|
|
{
|
|
/*
|
|
* if recovery_target_xid specified, then this overrides
|
|
* recovery_target_time
|
|
*/
|
|
if (recoveryTargetExact)
|
|
continue;
|
|
recoveryTarget = true;
|
|
recoveryTargetExact = false;
|
|
|
|
/*
|
|
* Convert the time string given by the user to the time_t
|
|
* format. We use type abstime's input converter because we
|
|
* know abstime has the same representation as time_t.
|
|
*/
|
|
recoveryTargetTime = (time_t)
|
|
DatumGetAbsoluteTime(DirectFunctionCall1(abstimein,
|
|
CStringGetDatum(tok2)));
|
|
ereport(LOG,
|
|
(errmsg("recovery_target_time = %s",
|
|
DatumGetCString(DirectFunctionCall1(abstimeout,
|
|
AbsoluteTimeGetDatum((AbsoluteTime) recoveryTargetTime))))));
|
|
}
|
|
else if (strcmp(tok1, "recovery_target_inclusive") == 0)
|
|
{
|
|
/*
|
|
* does nothing if a recovery_target is not also set
|
|
*/
|
|
if (strcmp(tok2, "true") == 0)
|
|
recoveryTargetInclusive = true;
|
|
else
|
|
{
|
|
recoveryTargetInclusive = false;
|
|
tok2 = "false";
|
|
}
|
|
ereport(LOG,
|
|
(errmsg("recovery_target_inclusive = %s", tok2)));
|
|
}
|
|
else
|
|
ereport(FATAL,
|
|
(errmsg("unrecognized recovery parameter \"%s\"",
|
|
tok1)));
|
|
}
|
|
|
|
FreeFile(fd);
|
|
|
|
if (syntaxError)
|
|
ereport(FATAL,
|
|
(errmsg("syntax error in recovery command file: %s",
|
|
cmdline),
|
|
errhint("Lines should have the format parameter = 'value'.")));
|
|
|
|
/* Check that required parameters were supplied */
|
|
if (recoveryRestoreCommand == NULL)
|
|
ereport(FATAL,
|
|
(errmsg("recovery command file \"%s\" did not specify restore_command",
|
|
recoveryCommandFile)));
|
|
|
|
/* Enable fetching from archive recovery area */
|
|
InArchiveRecovery = true;
|
|
|
|
/*
|
|
* If user specified recovery_target_timeline, validate it or compute
|
|
* the "latest" value. We can't do this until after we've gotten the
|
|
* restore command and set InArchiveRecovery, because we need to fetch
|
|
* timeline history files from the archive.
|
|
*/
|
|
if (rtliGiven)
|
|
{
|
|
if (rtli)
|
|
{
|
|
/* Timeline 1 does not have a history file, all else should */
|
|
if (rtli != 1 && !existsTimeLineHistory(rtli))
|
|
ereport(FATAL,
|
|
(errmsg("recovery_target_timeline %u does not exist",
|
|
rtli)));
|
|
recoveryTargetTLI = rtli;
|
|
}
|
|
else
|
|
{
|
|
/* We start the "latest" search from pg_control's timeline */
|
|
recoveryTargetTLI = findNewestTimeLine(recoveryTargetTLI);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Exit archive-recovery state
|
|
*/
|
|
static void
|
|
exitArchiveRecovery(TimeLineID endTLI, uint32 endLogId, uint32 endLogSeg)
|
|
{
|
|
char recoveryPath[MAXPGPATH];
|
|
char xlogpath[MAXPGPATH];
|
|
char recoveryCommandFile[MAXPGPATH];
|
|
char recoveryCommandDone[MAXPGPATH];
|
|
|
|
/*
|
|
* We are no longer in archive recovery state.
|
|
*/
|
|
InArchiveRecovery = false;
|
|
|
|
/*
|
|
* We should have the ending log segment currently open. Verify, and
|
|
* then close it (to avoid problems on Windows with trying to rename
|
|
* or delete an open file).
|
|
*/
|
|
Assert(readFile >= 0);
|
|
Assert(readId == endLogId);
|
|
Assert(readSeg == endLogSeg);
|
|
|
|
close(readFile);
|
|
readFile = -1;
|
|
|
|
/*
|
|
* If the segment was fetched from archival storage, we want to
|
|
* replace the existing xlog segment (if any) with the archival
|
|
* version. This is because whatever is in XLogDir is very possibly
|
|
* older than what we have from the archives, since it could have come
|
|
* from restoring a PGDATA backup. In any case, the archival version
|
|
* certainly is more descriptive of what our current database state
|
|
* is, because that is what we replayed from.
|
|
*
|
|
* Note that if we are establishing a new timeline, ThisTimeLineID is
|
|
* already set to the new value, and so we will create a new file
|
|
* instead of overwriting any existing file.
|
|
*/
|
|
snprintf(recoveryPath, MAXPGPATH, "%s/RECOVERYXLOG", XLogDir);
|
|
XLogFilePath(xlogpath, ThisTimeLineID, endLogId, endLogSeg);
|
|
|
|
if (restoredFromArchive)
|
|
{
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("moving last restored xlog to \"%s\"",
|
|
xlogpath)));
|
|
unlink(xlogpath); /* might or might not exist */
|
|
if (rename(recoveryPath, xlogpath) != 0)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not rename file \"%s\" to \"%s\": %m",
|
|
recoveryPath, xlogpath)));
|
|
/* XXX might we need to fix permissions on the file? */
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* If the latest segment is not archival, but there's still a
|
|
* RECOVERYXLOG laying about, get rid of it.
|
|
*/
|
|
unlink(recoveryPath); /* ignore any error */
|
|
|
|
/*
|
|
* If we are establishing a new timeline, we have to copy data
|
|
* from the last WAL segment of the old timeline to create a
|
|
* starting WAL segment for the new timeline.
|
|
*/
|
|
if (endTLI != ThisTimeLineID)
|
|
XLogFileCopy(endLogId, endLogSeg,
|
|
endTLI, endLogId, endLogSeg);
|
|
}
|
|
|
|
/*
|
|
* Let's just make real sure there are not .ready or .done flags
|
|
* posted for the new segment.
|
|
*/
|
|
XLogFileName(xlogpath, ThisTimeLineID, endLogId, endLogSeg);
|
|
XLogArchiveCleanup(xlogpath);
|
|
|
|
/* Get rid of any remaining recovered timeline-history file, too */
|
|
snprintf(recoveryPath, MAXPGPATH, "%s/RECOVERYHISTORY", XLogDir);
|
|
unlink(recoveryPath); /* ignore any error */
|
|
|
|
/*
|
|
* Rename the config file out of the way, so that we don't
|
|
* accidentally re-enter archive recovery mode in a subsequent crash.
|
|
*/
|
|
snprintf(recoveryCommandFile, MAXPGPATH, "%s/recovery.conf", DataDir);
|
|
snprintf(recoveryCommandDone, MAXPGPATH, "%s/recovery.done", DataDir);
|
|
unlink(recoveryCommandDone);
|
|
if (rename(recoveryCommandFile, recoveryCommandDone) != 0)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not rename file \"%s\" to \"%s\": %m",
|
|
recoveryCommandFile, recoveryCommandDone)));
|
|
|
|
ereport(LOG,
|
|
(errmsg("archive recovery complete")));
|
|
}
|
|
|
|
/*
|
|
* For point-in-time recovery, this function decides whether we want to
|
|
* stop applying the XLOG at or after the current record.
|
|
*
|
|
* Returns TRUE if we are stopping, FALSE otherwise. On TRUE return,
|
|
* *includeThis is set TRUE if we should apply this record before stopping.
|
|
* Also, some information is saved in recoveryStopXid et al for use in
|
|
* annotating the new timeline's history file.
|
|
*/
|
|
static bool
|
|
recoveryStopsHere(XLogRecord *record, bool *includeThis)
|
|
{
|
|
bool stopsHere;
|
|
uint8 record_info;
|
|
time_t recordXtime;
|
|
|
|
/* Do we have a PITR target at all? */
|
|
if (!recoveryTarget)
|
|
return false;
|
|
|
|
/* We only consider stopping at COMMIT or ABORT records */
|
|
if (record->xl_rmid != RM_XACT_ID)
|
|
return false;
|
|
record_info = record->xl_info & ~XLR_INFO_MASK;
|
|
if (record_info == XLOG_XACT_COMMIT)
|
|
{
|
|
xl_xact_commit *recordXactCommitData;
|
|
|
|
recordXactCommitData = (xl_xact_commit *) XLogRecGetData(record);
|
|
recordXtime = recordXactCommitData->xtime;
|
|
}
|
|
else if (record_info == XLOG_XACT_ABORT)
|
|
{
|
|
xl_xact_abort *recordXactAbortData;
|
|
|
|
recordXactAbortData = (xl_xact_abort *) XLogRecGetData(record);
|
|
recordXtime = recordXactAbortData->xtime;
|
|
}
|
|
else
|
|
return false;
|
|
|
|
if (recoveryTargetExact)
|
|
{
|
|
/*
|
|
* there can be only one transaction end record with this exact
|
|
* transactionid
|
|
*
|
|
* when testing for an xid, we MUST test for equality only, since
|
|
* transactions are numbered in the order they start, not the
|
|
* order they complete. A higher numbered xid will complete before
|
|
* you about 50% of the time...
|
|
*/
|
|
stopsHere = (record->xl_xid == recoveryTargetXid);
|
|
if (stopsHere)
|
|
*includeThis = recoveryTargetInclusive;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* there can be many transactions that share the same commit time,
|
|
* so we stop after the last one, if we are inclusive, or stop at
|
|
* the first one if we are exclusive
|
|
*/
|
|
if (recoveryTargetInclusive)
|
|
stopsHere = (recordXtime > recoveryTargetTime);
|
|
else
|
|
stopsHere = (recordXtime >= recoveryTargetTime);
|
|
if (stopsHere)
|
|
*includeThis = false;
|
|
}
|
|
|
|
if (stopsHere)
|
|
{
|
|
recoveryStopXid = record->xl_xid;
|
|
recoveryStopTime = recordXtime;
|
|
recoveryStopAfter = *includeThis;
|
|
|
|
if (record_info == XLOG_XACT_COMMIT)
|
|
{
|
|
if (recoveryStopAfter)
|
|
ereport(LOG,
|
|
(errmsg("recovery stopping after commit of transaction %u, time %s",
|
|
recoveryStopXid, str_time(recoveryStopTime))));
|
|
else
|
|
ereport(LOG,
|
|
(errmsg("recovery stopping before commit of transaction %u, time %s",
|
|
recoveryStopXid, str_time(recoveryStopTime))));
|
|
}
|
|
else
|
|
{
|
|
if (recoveryStopAfter)
|
|
ereport(LOG,
|
|
(errmsg("recovery stopping after abort of transaction %u, time %s",
|
|
recoveryStopXid, str_time(recoveryStopTime))));
|
|
else
|
|
ereport(LOG,
|
|
(errmsg("recovery stopping before abort of transaction %u, time %s",
|
|
recoveryStopXid, str_time(recoveryStopTime))));
|
|
}
|
|
}
|
|
|
|
return stopsHere;
|
|
}
|
|
|
|
/*
|
|
* This must be called ONCE during postmaster or standalone-backend startup
|
|
*/
|
|
void
|
|
StartupXLOG(void)
|
|
{
|
|
XLogCtlInsert *Insert;
|
|
CheckPoint checkPoint;
|
|
bool wasShutdown;
|
|
bool needNewTimeLine = false;
|
|
XLogRecPtr RecPtr,
|
|
LastRec,
|
|
checkPointLoc,
|
|
EndOfLog;
|
|
uint32 endLogId;
|
|
uint32 endLogSeg;
|
|
XLogRecord *record;
|
|
uint32 freespace;
|
|
|
|
CritSectionCount++;
|
|
|
|
/*
|
|
* Read control file and check XLOG status looks valid.
|
|
*
|
|
* Note: in most control paths, *ControlFile is already valid and we need
|
|
* not do ReadControlFile() here, but might as well do it to be sure.
|
|
*/
|
|
ReadControlFile();
|
|
|
|
if (ControlFile->logSeg == 0 ||
|
|
ControlFile->state < DB_SHUTDOWNED ||
|
|
ControlFile->state > DB_IN_PRODUCTION ||
|
|
!XRecOffIsValid(ControlFile->checkPoint.xrecoff))
|
|
ereport(FATAL,
|
|
(errmsg("control file contains invalid data")));
|
|
|
|
if (ControlFile->state == DB_SHUTDOWNED)
|
|
ereport(LOG,
|
|
(errmsg("database system was shut down at %s",
|
|
str_time(ControlFile->time))));
|
|
else if (ControlFile->state == DB_SHUTDOWNING)
|
|
ereport(LOG,
|
|
(errmsg("database system shutdown was interrupted at %s",
|
|
str_time(ControlFile->time))));
|
|
else if (ControlFile->state == DB_IN_RECOVERY)
|
|
ereport(LOG,
|
|
(errmsg("database system was interrupted while in recovery at %s",
|
|
str_time(ControlFile->time)),
|
|
errhint("This probably means that some data is corrupted and"
|
|
" you will have to use the last backup for recovery.")));
|
|
else if (ControlFile->state == DB_IN_PRODUCTION)
|
|
ereport(LOG,
|
|
(errmsg("database system was interrupted at %s",
|
|
str_time(ControlFile->time))));
|
|
|
|
/* This is just to allow attaching to startup process with a debugger */
|
|
#ifdef XLOG_REPLAY_DELAY
|
|
if (ControlFile->state != DB_SHUTDOWNED)
|
|
pg_usleep(60000000L);
|
|
#endif
|
|
|
|
/*
|
|
* Initialize on the assumption we want to recover to the same
|
|
* timeline that's active according to pg_control.
|
|
*/
|
|
recoveryTargetTLI = ControlFile->checkPointCopy.ThisTimeLineID;
|
|
|
|
/*
|
|
* Check for recovery control file, and if so set up state for offline
|
|
* recovery
|
|
*/
|
|
readRecoveryCommandFile();
|
|
|
|
/* Now we can determine the list of expected TLIs */
|
|
expectedTLIs = readTimeLineHistory(recoveryTargetTLI);
|
|
|
|
/*
|
|
* If pg_control's timeline is not in expectedTLIs, then we cannot
|
|
* proceed: the backup is not part of the history of the requested
|
|
* timeline.
|
|
*/
|
|
if (!list_member_int(expectedTLIs,
|
|
(int) ControlFile->checkPointCopy.ThisTimeLineID))
|
|
ereport(FATAL,
|
|
(errmsg("requested timeline %u is not a child of database system timeline %u",
|
|
recoveryTargetTLI,
|
|
ControlFile->checkPointCopy.ThisTimeLineID)));
|
|
|
|
if (read_backup_label(&checkPointLoc))
|
|
{
|
|
/*
|
|
* When a backup_label file is present, we want to roll forward
|
|
* from the checkpoint it identifies, rather than using
|
|
* pg_control.
|
|
*/
|
|
record = ReadCheckpointRecord(checkPointLoc, 0);
|
|
if (record != NULL)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("checkpoint record is at %X/%X",
|
|
checkPointLoc.xlogid, checkPointLoc.xrecoff)));
|
|
InRecovery = true; /* force recovery even if SHUTDOWNED */
|
|
}
|
|
else
|
|
{
|
|
ereport(PANIC,
|
|
(errmsg("could not locate required checkpoint record"),
|
|
errhint("If you are not restoring from a backup, try removing $PGDATA/backup_label.")));
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Get the last valid checkpoint record. If the latest one
|
|
* according to pg_control is broken, try the next-to-last one.
|
|
*/
|
|
checkPointLoc = ControlFile->checkPoint;
|
|
record = ReadCheckpointRecord(checkPointLoc, 1);
|
|
if (record != NULL)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("checkpoint record is at %X/%X",
|
|
checkPointLoc.xlogid, checkPointLoc.xrecoff)));
|
|
}
|
|
else
|
|
{
|
|
checkPointLoc = ControlFile->prevCheckPoint;
|
|
record = ReadCheckpointRecord(checkPointLoc, 2);
|
|
if (record != NULL)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("using previous checkpoint record at %X/%X",
|
|
checkPointLoc.xlogid, checkPointLoc.xrecoff)));
|
|
InRecovery = true; /* force recovery even if
|
|
* SHUTDOWNED */
|
|
}
|
|
else
|
|
ereport(PANIC,
|
|
(errmsg("could not locate a valid checkpoint record")));
|
|
}
|
|
}
|
|
|
|
LastRec = RecPtr = checkPointLoc;
|
|
memcpy(&checkPoint, XLogRecGetData(record), sizeof(CheckPoint));
|
|
wasShutdown = (record->xl_info == XLOG_CHECKPOINT_SHUTDOWN);
|
|
|
|
ereport(LOG,
|
|
(errmsg("redo record is at %X/%X; undo record is at %X/%X; shutdown %s",
|
|
checkPoint.redo.xlogid, checkPoint.redo.xrecoff,
|
|
checkPoint.undo.xlogid, checkPoint.undo.xrecoff,
|
|
wasShutdown ? "TRUE" : "FALSE")));
|
|
ereport(LOG,
|
|
(errmsg("next transaction ID: %u; next OID: %u",
|
|
checkPoint.nextXid, checkPoint.nextOid)));
|
|
if (!TransactionIdIsNormal(checkPoint.nextXid))
|
|
ereport(PANIC,
|
|
(errmsg("invalid next transaction ID")));
|
|
|
|
ShmemVariableCache->nextXid = checkPoint.nextXid;
|
|
ShmemVariableCache->nextOid = checkPoint.nextOid;
|
|
ShmemVariableCache->oidCount = 0;
|
|
|
|
/*
|
|
* We must replay WAL entries using the same TimeLineID they were
|
|
* created under, so temporarily adopt the TLI indicated by the
|
|
* checkpoint (see also xlog_redo()).
|
|
*/
|
|
ThisTimeLineID = checkPoint.ThisTimeLineID;
|
|
|
|
RedoRecPtr = XLogCtl->Insert.RedoRecPtr = checkPoint.redo;
|
|
|
|
if (XLByteLT(RecPtr, checkPoint.redo))
|
|
ereport(PANIC,
|
|
(errmsg("invalid redo in checkpoint record")));
|
|
if (checkPoint.undo.xrecoff == 0)
|
|
checkPoint.undo = RecPtr;
|
|
|
|
/*
|
|
* Check whether we need to force recovery from WAL. If it appears to
|
|
* have been a clean shutdown and we did not have a recovery.conf
|
|
* file, then assume no recovery needed.
|
|
*/
|
|
if (XLByteLT(checkPoint.undo, RecPtr) ||
|
|
XLByteLT(checkPoint.redo, RecPtr))
|
|
{
|
|
if (wasShutdown)
|
|
ereport(PANIC,
|
|
(errmsg("invalid redo/undo record in shutdown checkpoint")));
|
|
InRecovery = true;
|
|
}
|
|
else if (ControlFile->state != DB_SHUTDOWNED)
|
|
InRecovery = true;
|
|
else if (InArchiveRecovery)
|
|
{
|
|
/* force recovery due to presence of recovery.conf */
|
|
InRecovery = true;
|
|
}
|
|
|
|
/* REDO */
|
|
if (InRecovery)
|
|
{
|
|
int rmid;
|
|
|
|
if (InArchiveRecovery)
|
|
ereport(LOG,
|
|
(errmsg("automatic recovery in progress")));
|
|
else
|
|
ereport(LOG,
|
|
(errmsg("database system was not properly shut down; "
|
|
"automatic recovery in progress")));
|
|
ControlFile->state = DB_IN_RECOVERY;
|
|
ControlFile->time = time(NULL);
|
|
UpdateControlFile();
|
|
|
|
/* Start up the recovery environment */
|
|
XLogInitRelationCache();
|
|
|
|
for (rmid = 0; rmid <= RM_MAX_ID; rmid++)
|
|
{
|
|
if (RmgrTable[rmid].rm_startup != NULL)
|
|
RmgrTable[rmid].rm_startup();
|
|
}
|
|
|
|
/*
|
|
* Find the first record that logically follows the checkpoint ---
|
|
* it might physically precede it, though.
|
|
*/
|
|
if (XLByteLT(checkPoint.redo, RecPtr))
|
|
{
|
|
/* back up to find the record */
|
|
record = ReadRecord(&(checkPoint.redo), PANIC);
|
|
}
|
|
else
|
|
{
|
|
/* just have to read next record after CheckPoint */
|
|
record = ReadRecord(NULL, LOG);
|
|
}
|
|
|
|
if (record != NULL)
|
|
{
|
|
bool recoveryContinue = true;
|
|
bool recoveryApply = true;
|
|
|
|
InRedo = true;
|
|
ereport(LOG,
|
|
(errmsg("redo starts at %X/%X",
|
|
ReadRecPtr.xlogid, ReadRecPtr.xrecoff)));
|
|
|
|
/*
|
|
* main redo apply loop
|
|
*/
|
|
do
|
|
{
|
|
#ifdef WAL_DEBUG
|
|
if (XLOG_DEBUG)
|
|
{
|
|
char buf[8192];
|
|
|
|
sprintf(buf, "REDO @ %X/%X; LSN %X/%X: ",
|
|
ReadRecPtr.xlogid, ReadRecPtr.xrecoff,
|
|
EndRecPtr.xlogid, EndRecPtr.xrecoff);
|
|
xlog_outrec(buf, record);
|
|
strcat(buf, " - ");
|
|
RmgrTable[record->xl_rmid].rm_desc(buf,
|
|
record->xl_info, XLogRecGetData(record));
|
|
elog(LOG, "%s", buf);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Have we reached our recovery target?
|
|
*/
|
|
if (recoveryStopsHere(record, &recoveryApply))
|
|
{
|
|
needNewTimeLine = true; /* see below */
|
|
recoveryContinue = false;
|
|
if (!recoveryApply)
|
|
break;
|
|
}
|
|
|
|
/* nextXid must be beyond record's xid */
|
|
if (TransactionIdFollowsOrEquals(record->xl_xid,
|
|
ShmemVariableCache->nextXid))
|
|
{
|
|
ShmemVariableCache->nextXid = record->xl_xid;
|
|
TransactionIdAdvance(ShmemVariableCache->nextXid);
|
|
}
|
|
|
|
if (record->xl_info & XLR_BKP_BLOCK_MASK)
|
|
RestoreBkpBlocks(record, EndRecPtr);
|
|
|
|
RmgrTable[record->xl_rmid].rm_redo(EndRecPtr, record);
|
|
|
|
LastRec = ReadRecPtr;
|
|
|
|
record = ReadRecord(NULL, LOG);
|
|
} while (record != NULL && recoveryContinue);
|
|
|
|
/*
|
|
* end of main redo apply loop
|
|
*/
|
|
|
|
ereport(LOG,
|
|
(errmsg("redo done at %X/%X",
|
|
ReadRecPtr.xlogid, ReadRecPtr.xrecoff)));
|
|
InRedo = false;
|
|
}
|
|
else
|
|
{
|
|
/* there are no WAL records following the checkpoint */
|
|
ereport(LOG,
|
|
(errmsg("redo is not required")));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Re-fetch the last valid or last applied record, so we can identify
|
|
* the exact endpoint of what we consider the valid portion of WAL.
|
|
*/
|
|
record = ReadRecord(&LastRec, PANIC);
|
|
EndOfLog = EndRecPtr;
|
|
XLByteToPrevSeg(EndOfLog, endLogId, endLogSeg);
|
|
|
|
/*
|
|
* Complain if we did not roll forward far enough to render the backup
|
|
* dump consistent.
|
|
*/
|
|
if (XLByteLT(EndOfLog, recoveryMinXlogOffset))
|
|
{
|
|
if (needNewTimeLine) /* stopped because of stop request */
|
|
ereport(FATAL,
|
|
(errmsg("requested recovery stop point is before end time of backup dump")));
|
|
else
|
|
/* ran off end of WAL */
|
|
ereport(FATAL,
|
|
(errmsg("WAL ends before end time of backup dump")));
|
|
}
|
|
|
|
/*
|
|
* Consider whether we need to assign a new timeline ID.
|
|
*
|
|
* If we stopped short of the end of WAL during recovery, then we are
|
|
* generating a new timeline and must assign it a unique new ID.
|
|
* Otherwise, we can just extend the timeline we were in when we ran
|
|
* out of WAL.
|
|
*/
|
|
if (needNewTimeLine)
|
|
{
|
|
ThisTimeLineID = findNewestTimeLine(recoveryTargetTLI) + 1;
|
|
ereport(LOG,
|
|
(errmsg("selected new timeline ID: %u", ThisTimeLineID)));
|
|
writeTimeLineHistory(ThisTimeLineID, recoveryTargetTLI,
|
|
curFileTLI, endLogId, endLogSeg);
|
|
}
|
|
|
|
/* Save the selected TimeLineID in shared memory, too */
|
|
XLogCtl->ThisTimeLineID = ThisTimeLineID;
|
|
|
|
/*
|
|
* We are now done reading the old WAL. Turn off archive fetching if
|
|
* it was active, and make a writable copy of the last WAL segment.
|
|
* (Note that we also have a copy of the last block of the old WAL in
|
|
* readBuf; we will use that below.)
|
|
*/
|
|
if (InArchiveRecovery)
|
|
exitArchiveRecovery(curFileTLI, endLogId, endLogSeg);
|
|
|
|
/*
|
|
* Prepare to write WAL starting at EndOfLog position, and init xlog
|
|
* buffer cache using the block containing the last record from the
|
|
* previous incarnation.
|
|
*/
|
|
openLogId = endLogId;
|
|
openLogSeg = endLogSeg;
|
|
openLogFile = XLogFileOpen(openLogId, openLogSeg);
|
|
openLogOff = 0;
|
|
ControlFile->logId = openLogId;
|
|
ControlFile->logSeg = openLogSeg + 1;
|
|
Insert = &XLogCtl->Insert;
|
|
Insert->PrevRecord = LastRec;
|
|
XLogCtl->xlblocks[0].xlogid = openLogId;
|
|
XLogCtl->xlblocks[0].xrecoff =
|
|
((EndOfLog.xrecoff - 1) / BLCKSZ + 1) * BLCKSZ;
|
|
|
|
/*
|
|
* Tricky point here: readBuf contains the *last* block that the
|
|
* LastRec record spans, not the one it starts in. The last block is
|
|
* indeed the one we want to use.
|
|
*/
|
|
Assert(readOff == (XLogCtl->xlblocks[0].xrecoff - BLCKSZ) % XLogSegSize);
|
|
memcpy((char *) Insert->currpage, readBuf, BLCKSZ);
|
|
Insert->currpos = (char *) Insert->currpage +
|
|
(EndOfLog.xrecoff + BLCKSZ - XLogCtl->xlblocks[0].xrecoff);
|
|
|
|
LogwrtResult.Write = LogwrtResult.Flush = EndOfLog;
|
|
|
|
XLogCtl->Write.LogwrtResult = LogwrtResult;
|
|
Insert->LogwrtResult = LogwrtResult;
|
|
XLogCtl->LogwrtResult = LogwrtResult;
|
|
|
|
XLogCtl->LogwrtRqst.Write = EndOfLog;
|
|
XLogCtl->LogwrtRqst.Flush = EndOfLog;
|
|
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
if (freespace > 0)
|
|
{
|
|
/* Make sure rest of page is zero */
|
|
MemSet(Insert->currpos, 0, freespace);
|
|
XLogCtl->Write.curridx = 0;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Whenever Write.LogwrtResult points to exactly the end of a
|
|
* page, Write.curridx must point to the *next* page (see
|
|
* XLogWrite()).
|
|
*
|
|
* Note: it might seem we should do AdvanceXLInsertBuffer() here, but
|
|
* this is sufficient. The first actual attempt to insert a log
|
|
* record will advance the insert state.
|
|
*/
|
|
XLogCtl->Write.curridx = NextBufIdx(0);
|
|
}
|
|
|
|
#ifdef NOT_USED
|
|
/* UNDO */
|
|
if (InRecovery)
|
|
{
|
|
RecPtr = ReadRecPtr;
|
|
if (XLByteLT(checkPoint.undo, RecPtr))
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("undo starts at %X/%X",
|
|
RecPtr.xlogid, RecPtr.xrecoff)));
|
|
do
|
|
{
|
|
record = ReadRecord(&RecPtr, PANIC);
|
|
if (TransactionIdIsValid(record->xl_xid) &&
|
|
!TransactionIdDidCommit(record->xl_xid))
|
|
RmgrTable[record->xl_rmid].rm_undo(EndRecPtr, record);
|
|
RecPtr = record->xl_prev;
|
|
} while (XLByteLE(checkPoint.undo, RecPtr));
|
|
ereport(LOG,
|
|
(errmsg("undo done at %X/%X",
|
|
ReadRecPtr.xlogid, ReadRecPtr.xrecoff)));
|
|
}
|
|
else
|
|
ereport(LOG,
|
|
(errmsg("undo is not required")));
|
|
}
|
|
#endif
|
|
|
|
if (InRecovery)
|
|
{
|
|
int rmid;
|
|
|
|
/*
|
|
* Allow resource managers to do any required cleanup.
|
|
*/
|
|
for (rmid = 0; rmid <= RM_MAX_ID; rmid++)
|
|
{
|
|
if (RmgrTable[rmid].rm_cleanup != NULL)
|
|
RmgrTable[rmid].rm_cleanup();
|
|
}
|
|
|
|
/*
|
|
* Perform a new checkpoint to update our recovery activity to
|
|
* disk.
|
|
*
|
|
* Note that we write a shutdown checkpoint rather than an on-line
|
|
* one. This is not particularly critical, but since we may be
|
|
* assigning a new TLI, using a shutdown checkpoint allows us to
|
|
* have the rule that TLI only changes in shutdown checkpoints,
|
|
* which allows some extra error checking in xlog_redo.
|
|
*
|
|
* In case we had to use the secondary checkpoint, make sure that it
|
|
* will still be shown as the secondary checkpoint after this
|
|
* CreateCheckPoint operation; we don't want the broken primary
|
|
* checkpoint to become prevCheckPoint...
|
|
*/
|
|
if (XLByteEQ(checkPointLoc, ControlFile->prevCheckPoint))
|
|
ControlFile->checkPoint = checkPointLoc;
|
|
|
|
CreateCheckPoint(true, true);
|
|
|
|
/*
|
|
* Close down recovery environment
|
|
*/
|
|
XLogCloseRelationCache();
|
|
|
|
/*
|
|
* Now that we've checkpointed the recovery, it's safe to flush
|
|
* old backup_label, if present.
|
|
*/
|
|
remove_backup_label();
|
|
}
|
|
|
|
/*
|
|
* Preallocate additional log files, if wanted.
|
|
*/
|
|
PreallocXlogFiles(EndOfLog);
|
|
|
|
/*
|
|
* Okay, we're officially UP.
|
|
*/
|
|
InRecovery = false;
|
|
|
|
ControlFile->state = DB_IN_PRODUCTION;
|
|
ControlFile->time = time(NULL);
|
|
UpdateControlFile();
|
|
|
|
/* Start up the commit log, too */
|
|
StartupCLOG();
|
|
StartupSUBTRANS();
|
|
|
|
ereport(LOG,
|
|
(errmsg("database system is ready")));
|
|
CritSectionCount--;
|
|
|
|
/* Shut down readFile facility, free space */
|
|
if (readFile >= 0)
|
|
{
|
|
close(readFile);
|
|
readFile = -1;
|
|
}
|
|
if (readBuf)
|
|
{
|
|
free(readBuf);
|
|
readBuf = NULL;
|
|
}
|
|
if (readRecordBuf)
|
|
{
|
|
free(readRecordBuf);
|
|
readRecordBuf = NULL;
|
|
readRecordBufSize = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Subroutine to try to fetch and validate a prior checkpoint record.
|
|
*
|
|
* whichChkpt identifies the checkpoint (merely for reporting purposes).
|
|
* 1 for "primary", 2 for "secondary", 0 for "other" (backup_label)
|
|
*/
|
|
static XLogRecord *
|
|
ReadCheckpointRecord(XLogRecPtr RecPtr, int whichChkpt)
|
|
{
|
|
XLogRecord *record;
|
|
|
|
if (!XRecOffIsValid(RecPtr.xrecoff))
|
|
{
|
|
switch (whichChkpt)
|
|
{
|
|
case 1:
|
|
ereport(LOG,
|
|
(errmsg("invalid primary checkpoint link in control file")));
|
|
break;
|
|
case 2:
|
|
ereport(LOG,
|
|
(errmsg("invalid secondary checkpoint link in control file")));
|
|
break;
|
|
default:
|
|
ereport(LOG,
|
|
(errmsg("invalid checkpoint link in backup_label file")));
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
record = ReadRecord(&RecPtr, LOG);
|
|
|
|
if (record == NULL)
|
|
{
|
|
switch (whichChkpt)
|
|
{
|
|
case 1:
|
|
ereport(LOG,
|
|
(errmsg("invalid primary checkpoint record")));
|
|
break;
|
|
case 2:
|
|
ereport(LOG,
|
|
(errmsg("invalid secondary checkpoint record")));
|
|
break;
|
|
default:
|
|
ereport(LOG,
|
|
(errmsg("invalid checkpoint record")));
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
if (record->xl_rmid != RM_XLOG_ID)
|
|
{
|
|
switch (whichChkpt)
|
|
{
|
|
case 1:
|
|
ereport(LOG,
|
|
(errmsg("invalid resource manager ID in primary checkpoint record")));
|
|
break;
|
|
case 2:
|
|
ereport(LOG,
|
|
(errmsg("invalid resource manager ID in secondary checkpoint record")));
|
|
break;
|
|
default:
|
|
ereport(LOG,
|
|
(errmsg("invalid resource manager ID in checkpoint record")));
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
if (record->xl_info != XLOG_CHECKPOINT_SHUTDOWN &&
|
|
record->xl_info != XLOG_CHECKPOINT_ONLINE)
|
|
{
|
|
switch (whichChkpt)
|
|
{
|
|
case 1:
|
|
ereport(LOG,
|
|
(errmsg("invalid xl_info in primary checkpoint record")));
|
|
break;
|
|
case 2:
|
|
ereport(LOG,
|
|
(errmsg("invalid xl_info in secondary checkpoint record")));
|
|
break;
|
|
default:
|
|
ereport(LOG,
|
|
(errmsg("invalid xl_info in checkpoint record")));
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
if (record->xl_len != sizeof(CheckPoint))
|
|
{
|
|
switch (whichChkpt)
|
|
{
|
|
case 1:
|
|
ereport(LOG,
|
|
(errmsg("invalid length of primary checkpoint record")));
|
|
break;
|
|
case 2:
|
|
ereport(LOG,
|
|
(errmsg("invalid length of secondary checkpoint record")));
|
|
break;
|
|
default:
|
|
ereport(LOG,
|
|
(errmsg("invalid length of checkpoint record")));
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
return record;
|
|
}
|
|
|
|
/*
|
|
* This must be called during startup of a backend process, except that
|
|
* it need not be called in a standalone backend (which does StartupXLOG
|
|
* instead). We need to initialize the local copies of ThisTimeLineID and
|
|
* RedoRecPtr.
|
|
*
|
|
* Note: before Postgres 8.0, we went to some effort to keep the postmaster
|
|
* process's copies of ThisTimeLineID and RedoRecPtr valid too. This was
|
|
* unnecessary however, since the postmaster itself never touches XLOG anyway.
|
|
*/
|
|
void
|
|
InitXLOGAccess(void)
|
|
{
|
|
/* ThisTimeLineID doesn't change so we need no lock to copy it */
|
|
ThisTimeLineID = XLogCtl->ThisTimeLineID;
|
|
/* Use GetRedoRecPtr to copy the RedoRecPtr safely */
|
|
(void) GetRedoRecPtr();
|
|
}
|
|
|
|
/*
|
|
* Once spawned, a backend may update its local RedoRecPtr from
|
|
* XLogCtl->Insert.RedoRecPtr; it must hold the insert lock or info_lck
|
|
* to do so. This is done in XLogInsert() or GetRedoRecPtr().
|
|
*/
|
|
XLogRecPtr
|
|
GetRedoRecPtr(void)
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
Assert(XLByteLE(RedoRecPtr, xlogctl->Insert.RedoRecPtr));
|
|
RedoRecPtr = xlogctl->Insert.RedoRecPtr;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
|
|
return RedoRecPtr;
|
|
}
|
|
|
|
/*
|
|
* This must be called ONCE during postmaster or standalone-backend shutdown
|
|
*/
|
|
void
|
|
ShutdownXLOG(int code, Datum arg)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("shutting down")));
|
|
|
|
CritSectionCount++;
|
|
CreateCheckPoint(true, true);
|
|
ShutdownCLOG();
|
|
ShutdownSUBTRANS();
|
|
CritSectionCount--;
|
|
|
|
ereport(LOG,
|
|
(errmsg("database system is shut down")));
|
|
}
|
|
|
|
/*
|
|
* Perform a checkpoint --- either during shutdown, or on-the-fly
|
|
*
|
|
* If force is true, we force a checkpoint regardless of whether any XLOG
|
|
* activity has occurred since the last one.
|
|
*/
|
|
void
|
|
CreateCheckPoint(bool shutdown, bool force)
|
|
{
|
|
CheckPoint checkPoint;
|
|
XLogRecPtr recptr;
|
|
XLogCtlInsert *Insert = &XLogCtl->Insert;
|
|
XLogRecData rdata;
|
|
uint32 freespace;
|
|
uint32 _logId;
|
|
uint32 _logSeg;
|
|
|
|
/*
|
|
* Acquire CheckpointLock to ensure only one checkpoint happens at a
|
|
* time. (This is just pro forma, since in the present system
|
|
* structure there is only one process that is allowed to issue
|
|
* checkpoints at any given time.)
|
|
*/
|
|
LWLockAcquire(CheckpointLock, LW_EXCLUSIVE);
|
|
|
|
/*
|
|
* Use a critical section to force system panic if we have trouble.
|
|
*/
|
|
START_CRIT_SECTION();
|
|
|
|
if (shutdown)
|
|
{
|
|
ControlFile->state = DB_SHUTDOWNING;
|
|
ControlFile->time = time(NULL);
|
|
UpdateControlFile();
|
|
}
|
|
|
|
MemSet(&checkPoint, 0, sizeof(checkPoint));
|
|
checkPoint.ThisTimeLineID = ThisTimeLineID;
|
|
checkPoint.time = time(NULL);
|
|
|
|
/*
|
|
* We must hold CheckpointStartLock while determining the checkpoint
|
|
* REDO pointer. This ensures that any concurrent transaction commits
|
|
* will be either not yet logged, or logged and recorded in pg_clog.
|
|
* See notes in RecordTransactionCommit().
|
|
*/
|
|
LWLockAcquire(CheckpointStartLock, LW_EXCLUSIVE);
|
|
|
|
/* And we need WALInsertLock too */
|
|
LWLockAcquire(WALInsertLock, LW_EXCLUSIVE);
|
|
|
|
/*
|
|
* If this isn't a shutdown or forced checkpoint, and we have not
|
|
* inserted any XLOG records since the start of the last checkpoint,
|
|
* skip the checkpoint. The idea here is to avoid inserting duplicate
|
|
* checkpoints when the system is idle. That wastes log space, and
|
|
* more importantly it exposes us to possible loss of both current and
|
|
* previous checkpoint records if the machine crashes just as we're
|
|
* writing the update. (Perhaps it'd make even more sense to
|
|
* checkpoint only when the previous checkpoint record is in a
|
|
* different xlog page?)
|
|
*
|
|
* We have to make two tests to determine that nothing has happened since
|
|
* the start of the last checkpoint: current insertion point must
|
|
* match the end of the last checkpoint record, and its redo pointer
|
|
* must point to itself.
|
|
*/
|
|
if (!shutdown && !force)
|
|
{
|
|
XLogRecPtr curInsert;
|
|
|
|
INSERT_RECPTR(curInsert, Insert, Insert->curridx);
|
|
if (curInsert.xlogid == ControlFile->checkPoint.xlogid &&
|
|
curInsert.xrecoff == ControlFile->checkPoint.xrecoff +
|
|
MAXALIGN(SizeOfXLogRecord + sizeof(CheckPoint)) &&
|
|
ControlFile->checkPoint.xlogid ==
|
|
ControlFile->checkPointCopy.redo.xlogid &&
|
|
ControlFile->checkPoint.xrecoff ==
|
|
ControlFile->checkPointCopy.redo.xrecoff)
|
|
{
|
|
LWLockRelease(WALInsertLock);
|
|
LWLockRelease(CheckpointStartLock);
|
|
LWLockRelease(CheckpointLock);
|
|
END_CRIT_SECTION();
|
|
return;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Compute new REDO record ptr = location of next XLOG record.
|
|
*
|
|
* NB: this is NOT necessarily where the checkpoint record itself will
|
|
* be, since other backends may insert more XLOG records while we're
|
|
* off doing the buffer flush work. Those XLOG records are logically
|
|
* after the checkpoint, even though physically before it. Got that?
|
|
*/
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
if (freespace < SizeOfXLogRecord)
|
|
{
|
|
(void) AdvanceXLInsertBuffer();
|
|
/* OK to ignore update return flag, since we will do flush anyway */
|
|
freespace = INSERT_FREESPACE(Insert);
|
|
}
|
|
INSERT_RECPTR(checkPoint.redo, Insert, Insert->curridx);
|
|
|
|
/*
|
|
* Here we update the shared RedoRecPtr for future XLogInsert calls;
|
|
* this must be done while holding the insert lock AND the info_lck.
|
|
*
|
|
* Note: if we fail to complete the checkpoint, RedoRecPtr will be left
|
|
* pointing past where it really needs to point. This is okay; the
|
|
* only consequence is that XLogInsert might back up whole buffers
|
|
* that it didn't really need to. We can't postpone advancing
|
|
* RedoRecPtr because XLogInserts that happen while we are dumping
|
|
* buffers must assume that their buffer changes are not included in
|
|
* the checkpoint.
|
|
*/
|
|
{
|
|
/* use volatile pointer to prevent code rearrangement */
|
|
volatile XLogCtlData *xlogctl = XLogCtl;
|
|
|
|
SpinLockAcquire_NoHoldoff(&xlogctl->info_lck);
|
|
RedoRecPtr = xlogctl->Insert.RedoRecPtr = checkPoint.redo;
|
|
SpinLockRelease_NoHoldoff(&xlogctl->info_lck);
|
|
}
|
|
|
|
/*
|
|
* Get UNDO record ptr - this is oldest of PGPROC->logRec values. We
|
|
* do this while holding insert lock to ensure that we won't miss any
|
|
* about-to-commit transactions (UNDO must include all xacts that have
|
|
* commits after REDO point).
|
|
*
|
|
* XXX temporarily ifdef'd out to avoid three-way deadlock condition:
|
|
* GetUndoRecPtr needs to grab SInvalLock to ensure that it is looking
|
|
* at a stable set of proc records, but grabbing SInvalLock while
|
|
* holding WALInsertLock is no good. GetNewTransactionId may cause a
|
|
* WAL record to be written while holding XidGenLock, and
|
|
* GetSnapshotData needs to get XidGenLock while holding SInvalLock,
|
|
* so there's a risk of deadlock. Need to find a better solution. See
|
|
* pgsql-hackers discussion of 17-Dec-01.
|
|
*
|
|
* XXX actually, the whole UNDO code is dead code and unlikely to ever be
|
|
* revived, so the lack of a good solution here is not troubling.
|
|
*/
|
|
#ifdef NOT_USED
|
|
checkPoint.undo = GetUndoRecPtr();
|
|
|
|
if (shutdown && checkPoint.undo.xrecoff != 0)
|
|
elog(PANIC, "active transaction while database system is shutting down");
|
|
#endif
|
|
|
|
/*
|
|
* Now we can release insert lock and checkpoint start lock, allowing
|
|
* other xacts to proceed even while we are flushing disk buffers.
|
|
*/
|
|
LWLockRelease(WALInsertLock);
|
|
|
|
LWLockRelease(CheckpointStartLock);
|
|
|
|
/*
|
|
* Get the other info we need for the checkpoint record.
|
|
*/
|
|
LWLockAcquire(XidGenLock, LW_SHARED);
|
|
checkPoint.nextXid = ShmemVariableCache->nextXid;
|
|
LWLockRelease(XidGenLock);
|
|
|
|
LWLockAcquire(OidGenLock, LW_SHARED);
|
|
checkPoint.nextOid = ShmemVariableCache->nextOid;
|
|
if (!shutdown)
|
|
checkPoint.nextOid += ShmemVariableCache->oidCount;
|
|
LWLockRelease(OidGenLock);
|
|
|
|
/*
|
|
* Having constructed the checkpoint record, ensure all shmem disk
|
|
* buffers and commit-log buffers are flushed to disk.
|
|
*
|
|
* This I/O could fail for various reasons. If so, we will fail to
|
|
* complete the checkpoint, but there is no reason to force a system
|
|
* panic. Accordingly, exit critical section while doing it.
|
|
*/
|
|
END_CRIT_SECTION();
|
|
|
|
CheckPointCLOG();
|
|
CheckPointSUBTRANS();
|
|
FlushBufferPool();
|
|
|
|
START_CRIT_SECTION();
|
|
|
|
/*
|
|
* Now insert the checkpoint record into XLOG.
|
|
*/
|
|
rdata.buffer = InvalidBuffer;
|
|
rdata.data = (char *) (&checkPoint);
|
|
rdata.len = sizeof(checkPoint);
|
|
rdata.next = NULL;
|
|
|
|
recptr = XLogInsert(RM_XLOG_ID,
|
|
shutdown ? XLOG_CHECKPOINT_SHUTDOWN :
|
|
XLOG_CHECKPOINT_ONLINE,
|
|
&rdata);
|
|
|
|
XLogFlush(recptr);
|
|
|
|
/*
|
|
* We now have ProcLastRecPtr = start of actual checkpoint record,
|
|
* recptr = end of actual checkpoint record.
|
|
*/
|
|
if (shutdown && !XLByteEQ(checkPoint.redo, ProcLastRecPtr))
|
|
ereport(PANIC,
|
|
(errmsg("concurrent transaction log activity while database system is shutting down")));
|
|
|
|
/*
|
|
* Select point at which we can truncate the log, which we base on the
|
|
* prior checkpoint's earliest info.
|
|
*
|
|
* With UNDO support: oldest item is redo or undo, whichever is older;
|
|
* but watch out for case that undo = 0.
|
|
*
|
|
* Without UNDO support: just use the redo pointer. This allows xlog
|
|
* space to be freed much faster when there are long-running
|
|
* transactions.
|
|
*/
|
|
#ifdef NOT_USED
|
|
if (ControlFile->checkPointCopy.undo.xrecoff != 0 &&
|
|
XLByteLT(ControlFile->checkPointCopy.undo,
|
|
ControlFile->checkPointCopy.redo))
|
|
XLByteToSeg(ControlFile->checkPointCopy.undo, _logId, _logSeg);
|
|
else
|
|
#endif
|
|
XLByteToSeg(ControlFile->checkPointCopy.redo, _logId, _logSeg);
|
|
|
|
/*
|
|
* Update the control file.
|
|
*/
|
|
LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
|
|
if (shutdown)
|
|
ControlFile->state = DB_SHUTDOWNED;
|
|
ControlFile->prevCheckPoint = ControlFile->checkPoint;
|
|
ControlFile->checkPoint = ProcLastRecPtr;
|
|
ControlFile->checkPointCopy = checkPoint;
|
|
ControlFile->time = time(NULL);
|
|
UpdateControlFile();
|
|
LWLockRelease(ControlFileLock);
|
|
|
|
/*
|
|
* We are now done with critical updates; no need for system panic if
|
|
* we have trouble while fooling with offline log segments.
|
|
*/
|
|
END_CRIT_SECTION();
|
|
|
|
/*
|
|
* Delete offline log files (those no longer needed even for previous
|
|
* checkpoint).
|
|
*/
|
|
if (_logId || _logSeg)
|
|
{
|
|
PrevLogSeg(_logId, _logSeg);
|
|
MoveOfflineLogs(_logId, _logSeg, recptr);
|
|
}
|
|
|
|
/*
|
|
* Make more log segments if needed. (Do this after deleting offline
|
|
* log segments, to avoid having peak disk space usage higher than
|
|
* necessary.)
|
|
*/
|
|
if (!shutdown)
|
|
PreallocXlogFiles(recptr);
|
|
|
|
/*
|
|
* Truncate pg_subtrans if possible. We can throw away all data
|
|
* before the oldest XMIN of any running transaction. No future
|
|
* transaction will attempt to reference any pg_subtrans entry older
|
|
* than that (see Asserts in subtrans.c). During recovery, though, we
|
|
* mustn't do this because StartupSUBTRANS hasn't been called yet.
|
|
*/
|
|
if (!InRecovery)
|
|
TruncateSUBTRANS(GetOldestXmin(true));
|
|
|
|
LWLockRelease(CheckpointLock);
|
|
}
|
|
|
|
/*
|
|
* Write a NEXTOID log record
|
|
*/
|
|
void
|
|
XLogPutNextOid(Oid nextOid)
|
|
{
|
|
XLogRecData rdata;
|
|
|
|
rdata.buffer = InvalidBuffer;
|
|
rdata.data = (char *) (&nextOid);
|
|
rdata.len = sizeof(Oid);
|
|
rdata.next = NULL;
|
|
(void) XLogInsert(RM_XLOG_ID, XLOG_NEXTOID, &rdata);
|
|
}
|
|
|
|
/*
|
|
* XLOG resource manager's routines
|
|
*/
|
|
void
|
|
xlog_redo(XLogRecPtr lsn, XLogRecord *record)
|
|
{
|
|
uint8 info = record->xl_info & ~XLR_INFO_MASK;
|
|
|
|
if (info == XLOG_NEXTOID)
|
|
{
|
|
Oid nextOid;
|
|
|
|
memcpy(&nextOid, XLogRecGetData(record), sizeof(Oid));
|
|
if (ShmemVariableCache->nextOid < nextOid)
|
|
{
|
|
ShmemVariableCache->nextOid = nextOid;
|
|
ShmemVariableCache->oidCount = 0;
|
|
}
|
|
}
|
|
else if (info == XLOG_CHECKPOINT_SHUTDOWN)
|
|
{
|
|
CheckPoint checkPoint;
|
|
|
|
memcpy(&checkPoint, XLogRecGetData(record), sizeof(CheckPoint));
|
|
/* In a SHUTDOWN checkpoint, believe the counters exactly */
|
|
ShmemVariableCache->nextXid = checkPoint.nextXid;
|
|
ShmemVariableCache->nextOid = checkPoint.nextOid;
|
|
ShmemVariableCache->oidCount = 0;
|
|
|
|
/*
|
|
* TLI may change in a shutdown checkpoint, but it shouldn't
|
|
* decrease
|
|
*/
|
|
if (checkPoint.ThisTimeLineID != ThisTimeLineID)
|
|
{
|
|
if (checkPoint.ThisTimeLineID < ThisTimeLineID ||
|
|
!list_member_int(expectedTLIs,
|
|
(int) checkPoint.ThisTimeLineID))
|
|
ereport(PANIC,
|
|
(errmsg("unexpected timeline ID %u (after %u) in checkpoint record",
|
|
checkPoint.ThisTimeLineID, ThisTimeLineID)));
|
|
/* Following WAL records should be run with new TLI */
|
|
ThisTimeLineID = checkPoint.ThisTimeLineID;
|
|
}
|
|
}
|
|
else if (info == XLOG_CHECKPOINT_ONLINE)
|
|
{
|
|
CheckPoint checkPoint;
|
|
|
|
memcpy(&checkPoint, XLogRecGetData(record), sizeof(CheckPoint));
|
|
/* In an ONLINE checkpoint, treat the counters like NEXTOID */
|
|
if (TransactionIdPrecedes(ShmemVariableCache->nextXid,
|
|
checkPoint.nextXid))
|
|
ShmemVariableCache->nextXid = checkPoint.nextXid;
|
|
if (ShmemVariableCache->nextOid < checkPoint.nextOid)
|
|
{
|
|
ShmemVariableCache->nextOid = checkPoint.nextOid;
|
|
ShmemVariableCache->oidCount = 0;
|
|
}
|
|
/* TLI should not change in an on-line checkpoint */
|
|
if (checkPoint.ThisTimeLineID != ThisTimeLineID)
|
|
ereport(PANIC,
|
|
(errmsg("unexpected timeline ID %u (should be %u) in checkpoint record",
|
|
checkPoint.ThisTimeLineID, ThisTimeLineID)));
|
|
}
|
|
}
|
|
|
|
void
|
|
xlog_undo(XLogRecPtr lsn, XLogRecord *record)
|
|
{
|
|
}
|
|
|
|
void
|
|
xlog_desc(char *buf, uint8 xl_info, char *rec)
|
|
{
|
|
uint8 info = xl_info & ~XLR_INFO_MASK;
|
|
|
|
if (info == XLOG_CHECKPOINT_SHUTDOWN ||
|
|
info == XLOG_CHECKPOINT_ONLINE)
|
|
{
|
|
CheckPoint *checkpoint = (CheckPoint *) rec;
|
|
|
|
sprintf(buf + strlen(buf), "checkpoint: redo %X/%X; undo %X/%X; "
|
|
"tli %u; xid %u; oid %u; %s",
|
|
checkpoint->redo.xlogid, checkpoint->redo.xrecoff,
|
|
checkpoint->undo.xlogid, checkpoint->undo.xrecoff,
|
|
checkpoint->ThisTimeLineID, checkpoint->nextXid,
|
|
checkpoint->nextOid,
|
|
(info == XLOG_CHECKPOINT_SHUTDOWN) ? "shutdown" : "online");
|
|
}
|
|
else if (info == XLOG_NEXTOID)
|
|
{
|
|
Oid nextOid;
|
|
|
|
memcpy(&nextOid, rec, sizeof(Oid));
|
|
sprintf(buf + strlen(buf), "nextOid: %u", nextOid);
|
|
}
|
|
else
|
|
strcat(buf, "UNKNOWN");
|
|
}
|
|
|
|
#ifdef WAL_DEBUG
|
|
|
|
static void
|
|
xlog_outrec(char *buf, XLogRecord *record)
|
|
{
|
|
int bkpb;
|
|
int i;
|
|
|
|
sprintf(buf + strlen(buf), "prev %X/%X; xid %u",
|
|
record->xl_prev.xlogid, record->xl_prev.xrecoff,
|
|
record->xl_xid);
|
|
|
|
for (i = 0, bkpb = 0; i < XLR_MAX_BKP_BLOCKS; i++)
|
|
{
|
|
if (!(record->xl_info & (XLR_SET_BKP_BLOCK(i))))
|
|
continue;
|
|
bkpb++;
|
|
}
|
|
|
|
if (bkpb)
|
|
sprintf(buf + strlen(buf), "; bkpb %d", bkpb);
|
|
|
|
sprintf(buf + strlen(buf), ": %s",
|
|
RmgrTable[record->xl_rmid].rm_name);
|
|
}
|
|
#endif /* WAL_DEBUG */
|
|
|
|
|
|
/*
|
|
* GUC support
|
|
*/
|
|
const char *
|
|
assign_xlog_sync_method(const char *method, bool doit, GucSource source)
|
|
{
|
|
int new_sync_method;
|
|
int new_sync_bit;
|
|
|
|
if (pg_strcasecmp(method, "fsync") == 0)
|
|
{
|
|
new_sync_method = SYNC_METHOD_FSYNC;
|
|
new_sync_bit = 0;
|
|
}
|
|
#ifdef HAVE_FDATASYNC
|
|
else if (pg_strcasecmp(method, "fdatasync") == 0)
|
|
{
|
|
new_sync_method = SYNC_METHOD_FDATASYNC;
|
|
new_sync_bit = 0;
|
|
}
|
|
#endif
|
|
#ifdef OPEN_SYNC_FLAG
|
|
else if (pg_strcasecmp(method, "open_sync") == 0)
|
|
{
|
|
new_sync_method = SYNC_METHOD_OPEN;
|
|
new_sync_bit = OPEN_SYNC_FLAG;
|
|
}
|
|
#endif
|
|
#ifdef OPEN_DATASYNC_FLAG
|
|
else if (pg_strcasecmp(method, "open_datasync") == 0)
|
|
{
|
|
new_sync_method = SYNC_METHOD_OPEN;
|
|
new_sync_bit = OPEN_DATASYNC_FLAG;
|
|
}
|
|
#endif
|
|
else
|
|
return NULL;
|
|
|
|
if (!doit)
|
|
return method;
|
|
|
|
if (sync_method != new_sync_method || open_sync_bit != new_sync_bit)
|
|
{
|
|
/*
|
|
* To ensure that no blocks escape unsynced, force an fsync on the
|
|
* currently open log segment (if any). Also, if the open flag is
|
|
* changing, close the log file so it will be reopened (with new
|
|
* flag bit) at next use.
|
|
*/
|
|
if (openLogFile >= 0)
|
|
{
|
|
if (pg_fsync(openLogFile) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync log file %u, segment %u: %m",
|
|
openLogId, openLogSeg)));
|
|
if (open_sync_bit != new_sync_bit)
|
|
{
|
|
if (close(openLogFile))
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not close log file %u, segment %u: %m",
|
|
openLogId, openLogSeg)));
|
|
openLogFile = -1;
|
|
}
|
|
}
|
|
sync_method = new_sync_method;
|
|
open_sync_bit = new_sync_bit;
|
|
}
|
|
|
|
return method;
|
|
}
|
|
|
|
|
|
/*
|
|
* Issue appropriate kind of fsync (if any) on the current XLOG output file
|
|
*/
|
|
static void
|
|
issue_xlog_fsync(void)
|
|
{
|
|
switch (sync_method)
|
|
{
|
|
case SYNC_METHOD_FSYNC:
|
|
if (pg_fsync(openLogFile) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fsync log file %u, segment %u: %m",
|
|
openLogId, openLogSeg)));
|
|
break;
|
|
#ifdef HAVE_FDATASYNC
|
|
case SYNC_METHOD_FDATASYNC:
|
|
if (pg_fdatasync(openLogFile) != 0)
|
|
ereport(PANIC,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not fdatasync log file %u, segment %u: %m",
|
|
openLogId, openLogSeg)));
|
|
break;
|
|
#endif
|
|
case SYNC_METHOD_OPEN:
|
|
/* write synced it already */
|
|
break;
|
|
default:
|
|
elog(PANIC, "unrecognized wal_sync_method: %d", sync_method);
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* pg_start_backup: set up for taking an on-line backup dump
|
|
*
|
|
* Essentially what this does is to create a backup label file in $PGDATA,
|
|
* where it will be archived as part of the backup dump. The label file
|
|
* contains the user-supplied label string (typically this would be used
|
|
* to tell where the backup dump will be stored) and the starting time and
|
|
* starting WAL offset for the dump.
|
|
*/
|
|
Datum
|
|
pg_start_backup(PG_FUNCTION_ARGS)
|
|
{
|
|
text *backupid = PG_GETARG_TEXT_P(0);
|
|
text *result;
|
|
char *backupidstr;
|
|
XLogRecPtr checkpointloc;
|
|
XLogRecPtr startpoint;
|
|
time_t stamp_time;
|
|
char strfbuf[128];
|
|
char labelfilepath[MAXPGPATH];
|
|
char xlogfilename[MAXFNAMELEN];
|
|
uint32 _logId;
|
|
uint32 _logSeg;
|
|
struct stat stat_buf;
|
|
FILE *fp;
|
|
|
|
if (!superuser())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
(errmsg("must be superuser to run a backup"))));
|
|
backupidstr = DatumGetCString(DirectFunctionCall1(textout,
|
|
PointerGetDatum(backupid)));
|
|
|
|
/*
|
|
* Force a CHECKPOINT. This is not strictly necessary, but it seems
|
|
* like a good idea to minimize the amount of past WAL needed to use
|
|
* the backup. Also, this guarantees that two successive backup runs
|
|
* will have different checkpoint positions and hence different
|
|
* history file names, even if nothing happened in between.
|
|
*/
|
|
RequestCheckpoint(true);
|
|
|
|
/*
|
|
* Now we need to fetch the checkpoint record location, and also its
|
|
* REDO pointer. The oldest point in WAL that would be needed to
|
|
* restore starting from the checkpoint is precisely the REDO pointer.
|
|
*/
|
|
LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
|
|
checkpointloc = ControlFile->checkPoint;
|
|
startpoint = ControlFile->checkPointCopy.redo;
|
|
LWLockRelease(ControlFileLock);
|
|
|
|
XLByteToSeg(startpoint, _logId, _logSeg);
|
|
XLogFileName(xlogfilename, ThisTimeLineID, _logId, _logSeg);
|
|
|
|
/*
|
|
* We deliberately use strftime/localtime not the src/timezone
|
|
* functions, so that backup labels will consistently be recorded in
|
|
* the same timezone regardless of TimeZone setting. This matches
|
|
* elog.c's practice.
|
|
*/
|
|
stamp_time = time(NULL);
|
|
strftime(strfbuf, sizeof(strfbuf),
|
|
"%Y-%m-%d %H:%M:%S %Z",
|
|
localtime(&stamp_time));
|
|
|
|
/*
|
|
* Check for existing backup label --- implies a backup is already
|
|
* running
|
|
*/
|
|
snprintf(labelfilepath, MAXPGPATH, "%s/backup_label", DataDir);
|
|
if (stat(labelfilepath, &stat_buf) != 0)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not stat \"%s\": %m",
|
|
labelfilepath)));
|
|
}
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("a backup is already in progress"),
|
|
errhint("If you're sure there is no backup in progress, remove file \"%s\" and try again.",
|
|
labelfilepath)));
|
|
|
|
/*
|
|
* Okay, write the file
|
|
*/
|
|
fp = AllocateFile(labelfilepath, "w");
|
|
if (!fp)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m",
|
|
labelfilepath)));
|
|
fprintf(fp, "START WAL LOCATION: %X/%X (file %s)\n",
|
|
startpoint.xlogid, startpoint.xrecoff, xlogfilename);
|
|
fprintf(fp, "CHECKPOINT LOCATION: %X/%X\n",
|
|
checkpointloc.xlogid, checkpointloc.xrecoff);
|
|
fprintf(fp, "START TIME: %s\n", strfbuf);
|
|
fprintf(fp, "LABEL: %s\n", backupidstr);
|
|
if (fflush(fp) || ferror(fp) || FreeFile(fp))
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write file \"%s\": %m",
|
|
labelfilepath)));
|
|
|
|
/*
|
|
* We're done. As a convenience, return the starting WAL offset.
|
|
*/
|
|
snprintf(xlogfilename, sizeof(xlogfilename), "%X/%X",
|
|
startpoint.xlogid, startpoint.xrecoff);
|
|
result = DatumGetTextP(DirectFunctionCall1(textin,
|
|
CStringGetDatum(xlogfilename)));
|
|
PG_RETURN_TEXT_P(result);
|
|
}
|
|
|
|
/*
|
|
* pg_stop_backup: finish taking an on-line backup dump
|
|
*
|
|
* We remove the backup label file created by pg_start_backup, and instead
|
|
* create a backup history file in pg_xlog (whence it will immediately be
|
|
* archived). The backup history file contains the same info found in
|
|
* the label file, plus the backup-end time and WAL offset.
|
|
*/
|
|
Datum
|
|
pg_stop_backup(PG_FUNCTION_ARGS)
|
|
{
|
|
text *result;
|
|
XLogCtlInsert *Insert = &XLogCtl->Insert;
|
|
XLogRecPtr startpoint;
|
|
XLogRecPtr stoppoint;
|
|
time_t stamp_time;
|
|
char strfbuf[128];
|
|
char labelfilepath[MAXPGPATH];
|
|
char histfilepath[MAXPGPATH];
|
|
char startxlogfilename[MAXFNAMELEN];
|
|
char stopxlogfilename[MAXFNAMELEN];
|
|
uint32 _logId;
|
|
uint32 _logSeg;
|
|
FILE *lfp;
|
|
FILE *fp;
|
|
char ch;
|
|
int ich;
|
|
|
|
if (!superuser())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
(errmsg("must be superuser to run a backup"))));
|
|
|
|
/*
|
|
* Get the current end-of-WAL position; it will be unsafe to use this
|
|
* dump to restore to a point in advance of this time.
|
|
*/
|
|
LWLockAcquire(WALInsertLock, LW_EXCLUSIVE);
|
|
INSERT_RECPTR(stoppoint, Insert, Insert->curridx);
|
|
LWLockRelease(WALInsertLock);
|
|
|
|
XLByteToSeg(stoppoint, _logId, _logSeg);
|
|
XLogFileName(stopxlogfilename, ThisTimeLineID, _logId, _logSeg);
|
|
|
|
/*
|
|
* We deliberately use strftime/localtime not the src/timezone
|
|
* functions, so that backup labels will consistently be recorded in
|
|
* the same timezone regardless of TimeZone setting. This matches
|
|
* elog.c's practice.
|
|
*/
|
|
stamp_time = time(NULL);
|
|
strftime(strfbuf, sizeof(strfbuf),
|
|
"%Y-%m-%d %H:%M:%S %Z",
|
|
localtime(&stamp_time));
|
|
|
|
/*
|
|
* Open the existing label file
|
|
*/
|
|
snprintf(labelfilepath, MAXPGPATH, "%s/backup_label", DataDir);
|
|
lfp = AllocateFile(labelfilepath, "r");
|
|
if (!lfp)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m",
|
|
labelfilepath)));
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("a backup is not in progress")));
|
|
}
|
|
|
|
/*
|
|
* Read and parse the START WAL LOCATION line (this code is pretty
|
|
* crude, but we are not expecting any variability in the file
|
|
* format).
|
|
*/
|
|
if (fscanf(lfp, "START WAL LOCATION: %X/%X (file %24s)%c",
|
|
&startpoint.xlogid, &startpoint.xrecoff, startxlogfilename,
|
|
&ch) != 4 || ch != '\n')
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("invalid data in file \"%s\"", labelfilepath)));
|
|
|
|
/*
|
|
* Write the backup history file
|
|
*/
|
|
XLByteToSeg(startpoint, _logId, _logSeg);
|
|
BackupHistoryFilePath(histfilepath, ThisTimeLineID, _logId, _logSeg,
|
|
startpoint.xrecoff % XLogSegSize);
|
|
fp = AllocateFile(histfilepath, "w");
|
|
if (!fp)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m",
|
|
histfilepath)));
|
|
fprintf(fp, "START WAL LOCATION: %X/%X (file %s)\n",
|
|
startpoint.xlogid, startpoint.xrecoff, startxlogfilename);
|
|
fprintf(fp, "STOP WAL LOCATION: %X/%X (file %s)\n",
|
|
stoppoint.xlogid, stoppoint.xrecoff, stopxlogfilename);
|
|
/* transfer remaining lines from label to history file */
|
|
while ((ich = fgetc(lfp)) != EOF)
|
|
fputc(ich, fp);
|
|
fprintf(fp, "STOP TIME: %s\n", strfbuf);
|
|
if (fflush(fp) || ferror(fp) || FreeFile(fp))
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write file \"%s\": %m",
|
|
histfilepath)));
|
|
|
|
/*
|
|
* Close and remove the backup label file
|
|
*/
|
|
if (ferror(lfp) || FreeFile(lfp))
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m",
|
|
labelfilepath)));
|
|
if (unlink(labelfilepath) != 0)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not remove file \"%s\": %m",
|
|
labelfilepath)));
|
|
|
|
/*
|
|
* Notify archiver that history file may be archived immediately
|
|
*/
|
|
if (XLogArchivingActive())
|
|
{
|
|
BackupHistoryFileName(histfilepath, ThisTimeLineID, _logId, _logSeg,
|
|
startpoint.xrecoff % XLogSegSize);
|
|
XLogArchiveNotify(histfilepath);
|
|
}
|
|
|
|
/*
|
|
* We're done. As a convenience, return the ending WAL offset.
|
|
*/
|
|
snprintf(stopxlogfilename, sizeof(stopxlogfilename), "%X/%X",
|
|
stoppoint.xlogid, stoppoint.xrecoff);
|
|
result = DatumGetTextP(DirectFunctionCall1(textin,
|
|
CStringGetDatum(stopxlogfilename)));
|
|
PG_RETURN_TEXT_P(result);
|
|
}
|
|
|
|
/*
|
|
* read_backup_label: check to see if a backup_label file is present
|
|
*
|
|
* If we see a backup_label during recovery, we assume that we are recovering
|
|
* from a backup dump file, and we therefore roll forward from the checkpoint
|
|
* identified by the label file, NOT what pg_control says. This avoids the
|
|
* problem that pg_control might have been archived one or more checkpoints
|
|
* later than the start of the dump, and so if we rely on it as the start
|
|
* point, we will fail to restore a consistent database state.
|
|
*
|
|
* We also attempt to retrieve the corresponding backup history file.
|
|
* If successful, set recoveryMinXlogOffset to constrain valid PITR stopping
|
|
* points.
|
|
*
|
|
* Returns TRUE if a backup_label was found (and fills the checkpoint
|
|
* location into *checkPointLoc); returns FALSE if not.
|
|
*/
|
|
static bool
|
|
read_backup_label(XLogRecPtr *checkPointLoc)
|
|
{
|
|
XLogRecPtr startpoint;
|
|
XLogRecPtr stoppoint;
|
|
char labelfilepath[MAXPGPATH];
|
|
char histfilename[MAXFNAMELEN];
|
|
char histfilepath[MAXPGPATH];
|
|
char startxlogfilename[MAXFNAMELEN];
|
|
char stopxlogfilename[MAXFNAMELEN];
|
|
TimeLineID tli;
|
|
uint32 _logId;
|
|
uint32 _logSeg;
|
|
FILE *lfp;
|
|
FILE *fp;
|
|
char ch;
|
|
|
|
/*
|
|
* See if label file is present
|
|
*/
|
|
snprintf(labelfilepath, MAXPGPATH, "%s/backup_label", DataDir);
|
|
lfp = AllocateFile(labelfilepath, "r");
|
|
if (!lfp)
|
|
{
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m",
|
|
labelfilepath)));
|
|
return false; /* it's not there, all is fine */
|
|
}
|
|
|
|
/*
|
|
* Read and parse the START WAL LOCATION and CHECKPOINT lines (this
|
|
* code is pretty crude, but we are not expecting any variability in
|
|
* the file format).
|
|
*/
|
|
if (fscanf(lfp, "START WAL LOCATION: %X/%X (file %08X%16s)%c",
|
|
&startpoint.xlogid, &startpoint.xrecoff, &tli,
|
|
startxlogfilename, &ch) != 5 || ch != '\n')
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("invalid data in file \"%s\"", labelfilepath)));
|
|
if (fscanf(lfp, "CHECKPOINT LOCATION: %X/%X%c",
|
|
&checkPointLoc->xlogid, &checkPointLoc->xrecoff,
|
|
&ch) != 3 || ch != '\n')
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("invalid data in file \"%s\"", labelfilepath)));
|
|
if (ferror(lfp) || FreeFile(lfp))
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m",
|
|
labelfilepath)));
|
|
|
|
/*
|
|
* Try to retrieve the backup history file (no error if we can't)
|
|
*/
|
|
XLByteToSeg(startpoint, _logId, _logSeg);
|
|
BackupHistoryFileName(histfilename, tli, _logId, _logSeg,
|
|
startpoint.xrecoff % XLogSegSize);
|
|
|
|
if (InArchiveRecovery)
|
|
RestoreArchivedFile(histfilepath, histfilename, "RECOVERYHISTORY", 0);
|
|
else
|
|
BackupHistoryFilePath(histfilepath, tli, _logId, _logSeg,
|
|
startpoint.xrecoff % XLogSegSize);
|
|
|
|
fp = AllocateFile(histfilepath, "r");
|
|
if (fp)
|
|
{
|
|
/*
|
|
* Parse history file to identify stop point.
|
|
*/
|
|
if (fscanf(fp, "START WAL LOCATION: %X/%X (file %24s)%c",
|
|
&startpoint.xlogid, &startpoint.xrecoff, startxlogfilename,
|
|
&ch) != 4 || ch != '\n')
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("invalid data in file \"%s\"", histfilename)));
|
|
if (fscanf(fp, "STOP WAL LOCATION: %X/%X (file %24s)%c",
|
|
&stoppoint.xlogid, &stoppoint.xrecoff, stopxlogfilename,
|
|
&ch) != 4 || ch != '\n')
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("invalid data in file \"%s\"", histfilename)));
|
|
recoveryMinXlogOffset = stoppoint;
|
|
if (ferror(fp) || FreeFile(fp))
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read file \"%s\": %m",
|
|
histfilepath)));
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* remove_backup_label: remove any extant backup_label after successful
|
|
* recovery. Once we have completed the end-of-recovery checkpoint there
|
|
* is no reason to have to replay from the start point indicated by the
|
|
* label (and indeed we'll probably have removed/recycled the needed WAL
|
|
* segments), so remove the label to prevent trouble in later crash recoveries.
|
|
*/
|
|
static void
|
|
remove_backup_label(void)
|
|
{
|
|
char labelfilepath[MAXPGPATH];
|
|
|
|
snprintf(labelfilepath, MAXPGPATH, "%s/backup_label", DataDir);
|
|
if (unlink(labelfilepath) != 0)
|
|
if (errno != ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not remove file \"%s\": %m",
|
|
labelfilepath)));
|
|
}
|