3435 lines
98 KiB
C
3435 lines
98 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* vacuum.c
|
|
* The postgres vacuum cleaner.
|
|
*
|
|
* This file includes the "full" version of VACUUM, as well as control code
|
|
* used by all three of full VACUUM, lazy VACUUM, and ANALYZE. See
|
|
* vacuumlazy.c and analyze.c for the rest of the code for the latter two.
|
|
*
|
|
*
|
|
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
*
|
|
*
|
|
* IDENTIFICATION
|
|
* $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.310 2005/06/14 22:15:32 tgl Exp $
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
#include "postgres.h"
|
|
|
|
#include <sys/time.h>
|
|
#include <unistd.h>
|
|
|
|
#include "access/clog.h"
|
|
#include "access/genam.h"
|
|
#include "access/heapam.h"
|
|
#include "access/subtrans.h"
|
|
#include "access/xlog.h"
|
|
#include "catalog/catalog.h"
|
|
#include "catalog/namespace.h"
|
|
#include "catalog/pg_database.h"
|
|
#include "catalog/pg_index.h"
|
|
#include "commands/dbcommands.h"
|
|
#include "commands/vacuum.h"
|
|
#include "executor/executor.h"
|
|
#include "miscadmin.h"
|
|
#include "storage/freespace.h"
|
|
#include "storage/procarray.h"
|
|
#include "storage/smgr.h"
|
|
#include "tcop/pquery.h"
|
|
#include "utils/acl.h"
|
|
#include "utils/builtins.h"
|
|
#include "utils/fmgroids.h"
|
|
#include "utils/inval.h"
|
|
#include "utils/lsyscache.h"
|
|
#include "utils/memutils.h"
|
|
#include "utils/relcache.h"
|
|
#include "utils/syscache.h"
|
|
#include "pgstat.h"
|
|
|
|
|
|
typedef struct VacPageData
|
|
{
|
|
BlockNumber blkno; /* BlockNumber of this Page */
|
|
Size free; /* FreeSpace on this Page */
|
|
uint16 offsets_used; /* Number of OffNums used by vacuum */
|
|
uint16 offsets_free; /* Number of OffNums free or to be free */
|
|
OffsetNumber offsets[1]; /* Array of free OffNums */
|
|
} VacPageData;
|
|
|
|
typedef VacPageData *VacPage;
|
|
|
|
typedef struct VacPageListData
|
|
{
|
|
BlockNumber empty_end_pages; /* Number of "empty" end-pages */
|
|
int num_pages; /* Number of pages in pagedesc */
|
|
int num_allocated_pages; /* Number of allocated pages in
|
|
* pagedesc */
|
|
VacPage *pagedesc; /* Descriptions of pages */
|
|
} VacPageListData;
|
|
|
|
typedef VacPageListData *VacPageList;
|
|
|
|
typedef struct VTupleLinkData
|
|
{
|
|
ItemPointerData new_tid;
|
|
ItemPointerData this_tid;
|
|
} VTupleLinkData;
|
|
|
|
typedef VTupleLinkData *VTupleLink;
|
|
|
|
typedef struct VTupleMoveData
|
|
{
|
|
ItemPointerData tid; /* tuple ID */
|
|
VacPage vacpage; /* where to move */
|
|
bool cleanVpd; /* clean vacpage before using */
|
|
} VTupleMoveData;
|
|
|
|
typedef VTupleMoveData *VTupleMove;
|
|
|
|
typedef struct VRelStats
|
|
{
|
|
BlockNumber rel_pages;
|
|
double rel_tuples;
|
|
Size min_tlen;
|
|
Size max_tlen;
|
|
bool hasindex;
|
|
int num_vtlinks;
|
|
VTupleLink vtlinks;
|
|
} VRelStats;
|
|
|
|
/*----------------------------------------------------------------------
|
|
* ExecContext:
|
|
*
|
|
* As these variables always appear together, we put them into one struct
|
|
* and pull initialization and cleanup into separate routines.
|
|
* ExecContext is used by repair_frag() and move_xxx_tuple(). More
|
|
* accurately: It is *used* only in move_xxx_tuple(), but because this
|
|
* routine is called many times, we initialize the struct just once in
|
|
* repair_frag() and pass it on to move_xxx_tuple().
|
|
*/
|
|
typedef struct ExecContextData
|
|
{
|
|
ResultRelInfo *resultRelInfo;
|
|
EState *estate;
|
|
TupleTableSlot *slot;
|
|
} ExecContextData;
|
|
typedef ExecContextData *ExecContext;
|
|
|
|
static void
|
|
ExecContext_Init(ExecContext ec, Relation rel)
|
|
{
|
|
TupleDesc tupdesc = RelationGetDescr(rel);
|
|
|
|
/*
|
|
* We need a ResultRelInfo and an EState so we can use the regular
|
|
* executor's index-entry-making machinery.
|
|
*/
|
|
ec->estate = CreateExecutorState();
|
|
|
|
ec->resultRelInfo = makeNode(ResultRelInfo);
|
|
ec->resultRelInfo->ri_RangeTableIndex = 1; /* dummy */
|
|
ec->resultRelInfo->ri_RelationDesc = rel;
|
|
ec->resultRelInfo->ri_TrigDesc = NULL; /* we don't fire triggers */
|
|
|
|
ExecOpenIndices(ec->resultRelInfo);
|
|
|
|
ec->estate->es_result_relations = ec->resultRelInfo;
|
|
ec->estate->es_num_result_relations = 1;
|
|
ec->estate->es_result_relation_info = ec->resultRelInfo;
|
|
|
|
/* Set up a tuple slot too */
|
|
ec->slot = MakeSingleTupleTableSlot(tupdesc);
|
|
}
|
|
|
|
static void
|
|
ExecContext_Finish(ExecContext ec)
|
|
{
|
|
ExecDropSingleTupleTableSlot(ec->slot);
|
|
ExecCloseIndices(ec->resultRelInfo);
|
|
FreeExecutorState(ec->estate);
|
|
}
|
|
|
|
/*
|
|
* End of ExecContext Implementation
|
|
*----------------------------------------------------------------------
|
|
*/
|
|
|
|
static MemoryContext vac_context = NULL;
|
|
|
|
static int elevel = -1;
|
|
|
|
static TransactionId OldestXmin;
|
|
static TransactionId FreezeLimit;
|
|
|
|
|
|
/* non-export function prototypes */
|
|
static List *get_rel_oids(const RangeVar *vacrel, const char *stmttype);
|
|
static void vac_update_dbstats(Oid dbid,
|
|
TransactionId vacuumXID,
|
|
TransactionId frozenXID);
|
|
static void vac_truncate_clog(TransactionId vacuumXID,
|
|
TransactionId frozenXID);
|
|
static bool vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind);
|
|
static void full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt);
|
|
static void scan_heap(VRelStats *vacrelstats, Relation onerel,
|
|
VacPageList vacuum_pages, VacPageList fraged_pages);
|
|
static void repair_frag(VRelStats *vacrelstats, Relation onerel,
|
|
VacPageList vacuum_pages, VacPageList fraged_pages,
|
|
int nindexes, Relation *Irel);
|
|
static void move_chain_tuple(Relation rel,
|
|
Buffer old_buf, Page old_page, HeapTuple old_tup,
|
|
Buffer dst_buf, Page dst_page, VacPage dst_vacpage,
|
|
ExecContext ec, ItemPointer ctid, bool cleanVpd);
|
|
static void move_plain_tuple(Relation rel,
|
|
Buffer old_buf, Page old_page, HeapTuple old_tup,
|
|
Buffer dst_buf, Page dst_page, VacPage dst_vacpage,
|
|
ExecContext ec);
|
|
static void update_hint_bits(Relation rel, VacPageList fraged_pages,
|
|
int num_fraged_pages, BlockNumber last_move_dest_block,
|
|
int num_moved);
|
|
static void vacuum_heap(VRelStats *vacrelstats, Relation onerel,
|
|
VacPageList vacpagelist);
|
|
static void vacuum_page(Relation onerel, Buffer buffer, VacPage vacpage);
|
|
static void vacuum_index(VacPageList vacpagelist, Relation indrel,
|
|
double num_tuples, int keep_tuples);
|
|
static void scan_index(Relation indrel, double num_tuples);
|
|
static bool tid_reaped(ItemPointer itemptr, void *state);
|
|
static bool dummy_tid_reaped(ItemPointer itemptr, void *state);
|
|
static void vac_update_fsm(Relation onerel, VacPageList fraged_pages,
|
|
BlockNumber rel_pages);
|
|
static VacPage copy_vac_page(VacPage vacpage);
|
|
static void vpage_insert(VacPageList vacpagelist, VacPage vpnew);
|
|
static void *vac_bsearch(const void *key, const void *base,
|
|
size_t nelem, size_t size,
|
|
int (*compar) (const void *, const void *));
|
|
static int vac_cmp_blk(const void *left, const void *right);
|
|
static int vac_cmp_offno(const void *left, const void *right);
|
|
static int vac_cmp_vtlinks(const void *left, const void *right);
|
|
static bool enough_space(VacPage vacpage, Size len);
|
|
|
|
|
|
/****************************************************************************
|
|
* *
|
|
* Code common to all flavors of VACUUM and ANALYZE *
|
|
* *
|
|
****************************************************************************
|
|
*/
|
|
|
|
|
|
/*
|
|
* Primary entry point for VACUUM and ANALYZE commands.
|
|
*/
|
|
void
|
|
vacuum(VacuumStmt *vacstmt)
|
|
{
|
|
const char *stmttype = vacstmt->vacuum ? "VACUUM" : "ANALYZE";
|
|
TransactionId initialOldestXmin = InvalidTransactionId;
|
|
TransactionId initialFreezeLimit = InvalidTransactionId;
|
|
volatile MemoryContext anl_context = NULL;
|
|
volatile bool all_rels,
|
|
in_outer_xact,
|
|
use_own_xacts;
|
|
List *relations;
|
|
|
|
if (vacstmt->verbose)
|
|
elevel = INFO;
|
|
else
|
|
elevel = DEBUG2;
|
|
|
|
/*
|
|
* We cannot run VACUUM inside a user transaction block; if we were
|
|
* inside a transaction, then our commit- and
|
|
* start-transaction-command calls would not have the intended effect!
|
|
* Furthermore, the forced commit that occurs before truncating the
|
|
* relation's file would have the effect of committing the rest of the
|
|
* user's transaction too, which would certainly not be the desired
|
|
* behavior. (This only applies to VACUUM FULL, though. We could in
|
|
* theory run lazy VACUUM inside a transaction block, but we choose to
|
|
* disallow that case because we'd rather commit as soon as possible
|
|
* after finishing the vacuum. This is mainly so that we can let go
|
|
* the AccessExclusiveLock that we may be holding.)
|
|
*
|
|
* ANALYZE (without VACUUM) can run either way.
|
|
*/
|
|
if (vacstmt->vacuum)
|
|
{
|
|
PreventTransactionChain((void *) vacstmt, stmttype);
|
|
in_outer_xact = false;
|
|
}
|
|
else
|
|
in_outer_xact = IsInTransactionChain((void *) vacstmt);
|
|
|
|
/*
|
|
* Disallow the combination VACUUM FULL FREEZE; although it would mostly
|
|
* work, VACUUM FULL's ability to move tuples around means that it is
|
|
* injecting its own XID into tuple visibility checks. We'd have to
|
|
* guarantee that every moved tuple is properly marked XMIN_COMMITTED or
|
|
* XMIN_INVALID before the end of the operation. There are corner cases
|
|
* where this does not happen, and getting rid of them all seems hard
|
|
* (not to mention fragile to maintain). On the whole it's not worth it
|
|
* compared to telling people to use two operations. See pgsql-hackers
|
|
* discussion of 27-Nov-2004, and comments below for update_hint_bits().
|
|
*
|
|
* Note: this is enforced here, and not in the grammar, since (a) we can
|
|
* give a better error message, and (b) we might want to allow it again
|
|
* someday.
|
|
*/
|
|
if (vacstmt->vacuum && vacstmt->full && vacstmt->freeze)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("VACUUM FULL FREEZE is not supported"),
|
|
errhint("Use VACUUM FULL, then VACUUM FREEZE.")));
|
|
|
|
/*
|
|
* Send info about dead objects to the statistics collector
|
|
*/
|
|
if (vacstmt->vacuum)
|
|
pgstat_vacuum_tabstat();
|
|
|
|
/*
|
|
* Create special memory context for cross-transaction storage.
|
|
*
|
|
* Since it is a child of PortalContext, it will go away eventually even
|
|
* if we suffer an error; there's no need for special abort cleanup
|
|
* logic.
|
|
*/
|
|
vac_context = AllocSetContextCreate(PortalContext,
|
|
"Vacuum",
|
|
ALLOCSET_DEFAULT_MINSIZE,
|
|
ALLOCSET_DEFAULT_INITSIZE,
|
|
ALLOCSET_DEFAULT_MAXSIZE);
|
|
|
|
/* Assume we are processing everything unless one table is mentioned */
|
|
all_rels = (vacstmt->relation == NULL);
|
|
|
|
/* Build list of relations to process (note this lives in vac_context) */
|
|
relations = get_rel_oids(vacstmt->relation, stmttype);
|
|
|
|
if (vacstmt->vacuum && all_rels)
|
|
{
|
|
/*
|
|
* It's a database-wide VACUUM.
|
|
*
|
|
* Compute the initially applicable OldestXmin and FreezeLimit XIDs,
|
|
* so that we can record these values at the end of the VACUUM.
|
|
* Note that individual tables may well be processed with newer
|
|
* values, but we can guarantee that no (non-shared) relations are
|
|
* processed with older ones.
|
|
*
|
|
* It is okay to record non-shared values in pg_database, even though
|
|
* we may vacuum shared relations with older cutoffs, because only
|
|
* the minimum of the values present in pg_database matters. We
|
|
* can be sure that shared relations have at some time been
|
|
* vacuumed with cutoffs no worse than the global minimum; for, if
|
|
* there is a backend in some other DB with xmin = OLDXMIN that's
|
|
* determining the cutoff with which we vacuum shared relations,
|
|
* it is not possible for that database to have a cutoff newer
|
|
* than OLDXMIN recorded in pg_database.
|
|
*/
|
|
vacuum_set_xid_limits(vacstmt, false,
|
|
&initialOldestXmin,
|
|
&initialFreezeLimit);
|
|
}
|
|
|
|
/*
|
|
* Decide whether we need to start/commit our own transactions.
|
|
*
|
|
* For VACUUM (with or without ANALYZE): always do so, so that we can
|
|
* release locks as soon as possible. (We could possibly use the
|
|
* outer transaction for a one-table VACUUM, but handling TOAST tables
|
|
* would be problematic.)
|
|
*
|
|
* For ANALYZE (no VACUUM): if inside a transaction block, we cannot
|
|
* start/commit our own transactions. Also, there's no need to do so
|
|
* if only processing one relation. For multiple relations when not
|
|
* within a transaction block, use own transactions so we can release
|
|
* locks sooner.
|
|
*/
|
|
if (vacstmt->vacuum)
|
|
use_own_xacts = true;
|
|
else
|
|
{
|
|
Assert(vacstmt->analyze);
|
|
if (in_outer_xact)
|
|
use_own_xacts = false;
|
|
else if (list_length(relations) > 1)
|
|
use_own_xacts = true;
|
|
else
|
|
use_own_xacts = false;
|
|
}
|
|
|
|
/*
|
|
* If we are running ANALYZE without per-table transactions, we'll
|
|
* need a memory context with table lifetime.
|
|
*/
|
|
if (!use_own_xacts)
|
|
anl_context = AllocSetContextCreate(PortalContext,
|
|
"Analyze",
|
|
ALLOCSET_DEFAULT_MINSIZE,
|
|
ALLOCSET_DEFAULT_INITSIZE,
|
|
ALLOCSET_DEFAULT_MAXSIZE);
|
|
|
|
/*
|
|
* vacuum_rel expects to be entered with no transaction active; it
|
|
* will start and commit its own transaction. But we are called by an
|
|
* SQL command, and so we are executing inside a transaction already.
|
|
* We commit the transaction started in PostgresMain() here, and start
|
|
* another one before exiting to match the commit waiting for us back
|
|
* in PostgresMain().
|
|
*/
|
|
if (use_own_xacts)
|
|
{
|
|
/* matches the StartTransaction in PostgresMain() */
|
|
CommitTransactionCommand();
|
|
}
|
|
|
|
/* Turn vacuum cost accounting on or off */
|
|
PG_TRY();
|
|
{
|
|
ListCell *cur;
|
|
|
|
VacuumCostActive = (VacuumCostDelay > 0);
|
|
VacuumCostBalance = 0;
|
|
|
|
/*
|
|
* Loop to process each selected relation.
|
|
*/
|
|
foreach(cur, relations)
|
|
{
|
|
Oid relid = lfirst_oid(cur);
|
|
|
|
if (vacstmt->vacuum)
|
|
{
|
|
if (!vacuum_rel(relid, vacstmt, RELKIND_RELATION))
|
|
all_rels = false; /* forget about updating dbstats */
|
|
}
|
|
if (vacstmt->analyze)
|
|
{
|
|
MemoryContext old_context = NULL;
|
|
|
|
/*
|
|
* If using separate xacts, start one for analyze.
|
|
* Otherwise, we can use the outer transaction, but we
|
|
* still need to call analyze_rel in a memory context that
|
|
* will be cleaned up on return (else we leak memory while
|
|
* processing multiple tables).
|
|
*/
|
|
if (use_own_xacts)
|
|
{
|
|
StartTransactionCommand();
|
|
/* functions in indexes may want a snapshot set */
|
|
ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
|
|
}
|
|
else
|
|
old_context = MemoryContextSwitchTo(anl_context);
|
|
|
|
/*
|
|
* Tell the buffer replacement strategy that vacuum is
|
|
* causing the IO
|
|
*/
|
|
StrategyHintVacuum(true);
|
|
|
|
analyze_rel(relid, vacstmt);
|
|
|
|
StrategyHintVacuum(false);
|
|
|
|
if (use_own_xacts)
|
|
CommitTransactionCommand();
|
|
else
|
|
{
|
|
MemoryContextSwitchTo(old_context);
|
|
MemoryContextResetAndDeleteChildren(anl_context);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
PG_CATCH();
|
|
{
|
|
/* Make sure cost accounting is turned off after error */
|
|
VacuumCostActive = false;
|
|
PG_RE_THROW();
|
|
}
|
|
PG_END_TRY();
|
|
|
|
/* Turn off vacuum cost accounting */
|
|
VacuumCostActive = false;
|
|
|
|
/*
|
|
* Finish up processing.
|
|
*/
|
|
if (use_own_xacts)
|
|
{
|
|
/* here, we are not in a transaction */
|
|
|
|
/*
|
|
* This matches the CommitTransaction waiting for us in
|
|
* PostgresMain().
|
|
*/
|
|
StartTransactionCommand();
|
|
}
|
|
|
|
if (vacstmt->vacuum)
|
|
{
|
|
/*
|
|
* If it was a database-wide VACUUM, print FSM usage statistics
|
|
* (we don't make you be superuser to see these).
|
|
*/
|
|
if (vacstmt->relation == NULL)
|
|
PrintFreeSpaceMapStatistics(elevel);
|
|
|
|
/*
|
|
* If we completed a database-wide VACUUM without skipping any
|
|
* relations, update the database's pg_database row with info
|
|
* about the transaction IDs used, and try to truncate pg_clog.
|
|
*/
|
|
if (all_rels)
|
|
{
|
|
vac_update_dbstats(MyDatabaseId,
|
|
initialOldestXmin, initialFreezeLimit);
|
|
vac_truncate_clog(initialOldestXmin, initialFreezeLimit);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Clean up working storage --- note we must do this after
|
|
* StartTransactionCommand, else we might be trying to delete the
|
|
* active context!
|
|
*/
|
|
MemoryContextDelete(vac_context);
|
|
vac_context = NULL;
|
|
|
|
if (anl_context)
|
|
MemoryContextDelete(anl_context);
|
|
}
|
|
|
|
/*
|
|
* Build a list of Oids for each relation to be processed
|
|
*
|
|
* The list is built in vac_context so that it will survive across our
|
|
* per-relation transactions.
|
|
*/
|
|
static List *
|
|
get_rel_oids(const RangeVar *vacrel, const char *stmttype)
|
|
{
|
|
List *oid_list = NIL;
|
|
MemoryContext oldcontext;
|
|
|
|
if (vacrel)
|
|
{
|
|
/* Process a specific relation */
|
|
Oid relid;
|
|
|
|
relid = RangeVarGetRelid(vacrel, false);
|
|
|
|
/* Make a relation list entry for this guy */
|
|
oldcontext = MemoryContextSwitchTo(vac_context);
|
|
oid_list = lappend_oid(oid_list, relid);
|
|
MemoryContextSwitchTo(oldcontext);
|
|
}
|
|
else
|
|
{
|
|
/* Process all plain relations listed in pg_class */
|
|
Relation pgclass;
|
|
HeapScanDesc scan;
|
|
HeapTuple tuple;
|
|
ScanKeyData key;
|
|
|
|
ScanKeyInit(&key,
|
|
Anum_pg_class_relkind,
|
|
BTEqualStrategyNumber, F_CHAREQ,
|
|
CharGetDatum(RELKIND_RELATION));
|
|
|
|
pgclass = heap_open(RelationRelationId, AccessShareLock);
|
|
|
|
scan = heap_beginscan(pgclass, SnapshotNow, 1, &key);
|
|
|
|
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
|
|
{
|
|
/* Make a relation list entry for this guy */
|
|
oldcontext = MemoryContextSwitchTo(vac_context);
|
|
oid_list = lappend_oid(oid_list, HeapTupleGetOid(tuple));
|
|
MemoryContextSwitchTo(oldcontext);
|
|
}
|
|
|
|
heap_endscan(scan);
|
|
heap_close(pgclass, AccessShareLock);
|
|
}
|
|
|
|
return oid_list;
|
|
}
|
|
|
|
/*
|
|
* vacuum_set_xid_limits() -- compute oldest-Xmin and freeze cutoff points
|
|
*/
|
|
void
|
|
vacuum_set_xid_limits(VacuumStmt *vacstmt, bool sharedRel,
|
|
TransactionId *oldestXmin,
|
|
TransactionId *freezeLimit)
|
|
{
|
|
TransactionId limit;
|
|
|
|
*oldestXmin = GetOldestXmin(sharedRel);
|
|
|
|
Assert(TransactionIdIsNormal(*oldestXmin));
|
|
|
|
if (vacstmt->freeze)
|
|
{
|
|
/* FREEZE option: use oldest Xmin as freeze cutoff too */
|
|
limit = *oldestXmin;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Normal case: freeze cutoff is well in the past, to wit, about
|
|
* halfway to the wrap horizon
|
|
*/
|
|
limit = GetCurrentTransactionId() - (MaxTransactionId >> 2);
|
|
}
|
|
|
|
/*
|
|
* Be careful not to generate a "permanent" XID
|
|
*/
|
|
if (!TransactionIdIsNormal(limit))
|
|
limit = FirstNormalTransactionId;
|
|
|
|
/*
|
|
* Ensure sane relationship of limits
|
|
*/
|
|
if (TransactionIdFollows(limit, *oldestXmin))
|
|
{
|
|
ereport(WARNING,
|
|
(errmsg("oldest xmin is far in the past"),
|
|
errhint("Close open transactions soon to avoid wraparound problems.")));
|
|
limit = *oldestXmin;
|
|
}
|
|
|
|
*freezeLimit = limit;
|
|
}
|
|
|
|
|
|
/*
|
|
* vac_update_relstats() -- update statistics for one relation
|
|
*
|
|
* Update the whole-relation statistics that are kept in its pg_class
|
|
* row. There are additional stats that will be updated if we are
|
|
* doing ANALYZE, but we always update these stats. This routine works
|
|
* for both index and heap relation entries in pg_class.
|
|
*
|
|
* We violate no-overwrite semantics here by storing new values for the
|
|
* statistics columns directly into the pg_class tuple that's already on
|
|
* the page. The reason for this is that if we updated these tuples in
|
|
* the usual way, vacuuming pg_class itself wouldn't work very well ---
|
|
* by the time we got done with a vacuum cycle, most of the tuples in
|
|
* pg_class would've been obsoleted. Of course, this only works for
|
|
* fixed-size never-null columns, but these are.
|
|
*
|
|
* This routine is shared by full VACUUM, lazy VACUUM, and stand-alone
|
|
* ANALYZE.
|
|
*/
|
|
void
|
|
vac_update_relstats(Oid relid, BlockNumber num_pages, double num_tuples,
|
|
bool hasindex)
|
|
{
|
|
Relation rd;
|
|
HeapTupleData rtup;
|
|
HeapTuple ctup;
|
|
Form_pg_class pgcform;
|
|
Buffer buffer;
|
|
|
|
/*
|
|
* update number of tuples and number of pages in pg_class
|
|
*/
|
|
rd = heap_open(RelationRelationId, RowExclusiveLock);
|
|
|
|
ctup = SearchSysCache(RELOID,
|
|
ObjectIdGetDatum(relid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(ctup))
|
|
elog(ERROR, "pg_class entry for relid %u vanished during vacuuming",
|
|
relid);
|
|
|
|
/* get the buffer cache tuple */
|
|
rtup.t_self = ctup->t_self;
|
|
ReleaseSysCache(ctup);
|
|
if (!heap_fetch(rd, SnapshotNow, &rtup, &buffer, false, NULL))
|
|
elog(ERROR, "pg_class entry for relid %u vanished during vacuuming",
|
|
relid);
|
|
|
|
/* ensure no one else does this at the same time */
|
|
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
|
|
|
|
/* overwrite the existing statistics in the tuple */
|
|
pgcform = (Form_pg_class) GETSTRUCT(&rtup);
|
|
pgcform->relpages = (int32) num_pages;
|
|
pgcform->reltuples = (float4) num_tuples;
|
|
pgcform->relhasindex = hasindex;
|
|
|
|
/*
|
|
* If we have discovered that there are no indexes, then there's no
|
|
* primary key either. This could be done more thoroughly...
|
|
*/
|
|
if (!hasindex)
|
|
pgcform->relhaspkey = false;
|
|
|
|
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
|
|
|
|
/*
|
|
* Invalidate the tuple in the catcaches; this also arranges to flush
|
|
* the relation's relcache entry. (If we fail to commit for some
|
|
* reason, no flush will occur, but no great harm is done since there
|
|
* are no noncritical state updates here.)
|
|
*/
|
|
CacheInvalidateHeapTuple(rd, &rtup);
|
|
|
|
/* Write the buffer */
|
|
WriteBuffer(buffer);
|
|
|
|
heap_close(rd, RowExclusiveLock);
|
|
}
|
|
|
|
|
|
/*
|
|
* vac_update_dbstats() -- update statistics for one database
|
|
*
|
|
* Update the whole-database statistics that are kept in its pg_database
|
|
* row.
|
|
*
|
|
* We violate no-overwrite semantics here by storing new values for the
|
|
* statistics columns directly into the tuple that's already on the page.
|
|
* As with vac_update_relstats, this avoids leaving dead tuples behind
|
|
* after a VACUUM.
|
|
*
|
|
* This routine is shared by full and lazy VACUUM. Note that it is only
|
|
* applied after a database-wide VACUUM operation.
|
|
*
|
|
* Note that we don't bother to update the flat-file copy of pg_database.
|
|
*/
|
|
static void
|
|
vac_update_dbstats(Oid dbid,
|
|
TransactionId vacuumXID,
|
|
TransactionId frozenXID)
|
|
{
|
|
Relation relation;
|
|
ScanKeyData entry[1];
|
|
HeapScanDesc scan;
|
|
HeapTuple tuple;
|
|
Form_pg_database dbform;
|
|
|
|
relation = heap_open(DatabaseRelationId, RowExclusiveLock);
|
|
|
|
/* Must use a heap scan, since there's no syscache for pg_database */
|
|
ScanKeyInit(&entry[0],
|
|
ObjectIdAttributeNumber,
|
|
BTEqualStrategyNumber, F_OIDEQ,
|
|
ObjectIdGetDatum(dbid));
|
|
|
|
scan = heap_beginscan(relation, SnapshotNow, 1, entry);
|
|
|
|
tuple = heap_getnext(scan, ForwardScanDirection);
|
|
|
|
if (!HeapTupleIsValid(tuple))
|
|
elog(ERROR, "could not find tuple for database %u", dbid);
|
|
|
|
/* ensure no one else does this at the same time */
|
|
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_EXCLUSIVE);
|
|
|
|
dbform = (Form_pg_database) GETSTRUCT(tuple);
|
|
|
|
/* overwrite the existing statistics in the tuple */
|
|
dbform->datvacuumxid = vacuumXID;
|
|
dbform->datfrozenxid = frozenXID;
|
|
|
|
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
|
|
|
|
/* invalidate the tuple in the cache and write the buffer */
|
|
CacheInvalidateHeapTuple(relation, tuple);
|
|
WriteNoReleaseBuffer(scan->rs_cbuf);
|
|
|
|
heap_endscan(scan);
|
|
|
|
heap_close(relation, RowExclusiveLock);
|
|
}
|
|
|
|
|
|
/*
|
|
* vac_truncate_clog() -- attempt to truncate the commit log
|
|
*
|
|
* Scan pg_database to determine the system-wide oldest datvacuumxid,
|
|
* and use it to truncate the transaction commit log (pg_clog).
|
|
* Also update the XID wrap limit point maintained by varsup.c.
|
|
*
|
|
* We also generate a warning if the system-wide oldest datfrozenxid
|
|
* seems to be in danger of wrapping around. This is a long-in-advance
|
|
* warning; if we start getting uncomfortably close, GetNewTransactionId
|
|
* will generate more-annoying warnings, and ultimately refuse to issue
|
|
* any more new XIDs.
|
|
*
|
|
* The passed XIDs are simply the ones I just wrote into my pg_database
|
|
* entry. They're used to initialize the "min" calculations.
|
|
*
|
|
* This routine is shared by full and lazy VACUUM. Note that it is only
|
|
* applied after a database-wide VACUUM operation.
|
|
*/
|
|
static void
|
|
vac_truncate_clog(TransactionId vacuumXID, TransactionId frozenXID)
|
|
{
|
|
TransactionId myXID = GetCurrentTransactionId();
|
|
Relation relation;
|
|
HeapScanDesc scan;
|
|
HeapTuple tuple;
|
|
int32 age;
|
|
NameData oldest_datname;
|
|
bool vacuumAlreadyWrapped = false;
|
|
bool frozenAlreadyWrapped = false;
|
|
|
|
/* init oldest_datname to sync with my frozenXID */
|
|
namestrcpy(&oldest_datname, get_database_name(MyDatabaseId));
|
|
|
|
/*
|
|
* Note: the "already wrapped" cases should now be impossible due to the
|
|
* defenses in GetNewTransactionId, but we keep them anyway.
|
|
*/
|
|
relation = heap_open(DatabaseRelationId, AccessShareLock);
|
|
|
|
scan = heap_beginscan(relation, SnapshotNow, 0, NULL);
|
|
|
|
while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
|
|
{
|
|
Form_pg_database dbform = (Form_pg_database) GETSTRUCT(tuple);
|
|
|
|
/* Ignore non-connectable databases (eg, template0) */
|
|
/* It's assumed that these have been frozen correctly */
|
|
if (!dbform->datallowconn)
|
|
continue;
|
|
|
|
if (TransactionIdIsNormal(dbform->datvacuumxid))
|
|
{
|
|
if (TransactionIdPrecedes(myXID, dbform->datvacuumxid))
|
|
vacuumAlreadyWrapped = true;
|
|
else if (TransactionIdPrecedes(dbform->datvacuumxid, vacuumXID))
|
|
vacuumXID = dbform->datvacuumxid;
|
|
}
|
|
if (TransactionIdIsNormal(dbform->datfrozenxid))
|
|
{
|
|
if (TransactionIdPrecedes(myXID, dbform->datfrozenxid))
|
|
frozenAlreadyWrapped = true;
|
|
else if (TransactionIdPrecedes(dbform->datfrozenxid, frozenXID))
|
|
{
|
|
frozenXID = dbform->datfrozenxid;
|
|
namecpy(&oldest_datname, &dbform->datname);
|
|
}
|
|
}
|
|
}
|
|
|
|
heap_endscan(scan);
|
|
|
|
heap_close(relation, AccessShareLock);
|
|
|
|
/*
|
|
* Do not truncate CLOG if we seem to have suffered wraparound
|
|
* already; the computed minimum XID might be bogus.
|
|
*/
|
|
if (vacuumAlreadyWrapped)
|
|
{
|
|
ereport(WARNING,
|
|
(errmsg("some databases have not been vacuumed in over 2 billion transactions"),
|
|
errdetail("You may have already suffered transaction-wraparound data loss.")));
|
|
return;
|
|
}
|
|
|
|
/* Truncate CLOG to the oldest vacuumxid */
|
|
TruncateCLOG(vacuumXID);
|
|
|
|
/*
|
|
* Do not update varsup.c if we seem to have suffered wraparound
|
|
* already; the computed XID might be bogus.
|
|
*/
|
|
if (frozenAlreadyWrapped)
|
|
{
|
|
ereport(WARNING,
|
|
(errmsg("some databases have not been vacuumed in over 1 billion transactions"),
|
|
errhint("Better vacuum them soon, or you may have a wraparound failure.")));
|
|
return;
|
|
}
|
|
|
|
/* Update the wrap limit for GetNewTransactionId */
|
|
SetTransactionIdLimit(frozenXID, &oldest_datname);
|
|
|
|
/* Give warning about impending wraparound problems */
|
|
age = (int32) (myXID - frozenXID);
|
|
if (age > (int32) ((MaxTransactionId >> 3) * 3))
|
|
ereport(WARNING,
|
|
(errmsg("database \"%s\" must be vacuumed within %u transactions",
|
|
NameStr(oldest_datname),
|
|
(MaxTransactionId >> 1) - age),
|
|
errhint("To avoid a database shutdown, execute a full-database VACUUM in \"%s\".",
|
|
NameStr(oldest_datname))));
|
|
}
|
|
|
|
|
|
/****************************************************************************
|
|
* *
|
|
* Code common to both flavors of VACUUM *
|
|
* *
|
|
****************************************************************************
|
|
*/
|
|
|
|
|
|
/*
|
|
* vacuum_rel() -- vacuum one heap relation
|
|
*
|
|
* Returns TRUE if we actually processed the relation (or can ignore it
|
|
* for some reason), FALSE if we failed to process it due to permissions
|
|
* or other reasons. (A FALSE result really means that some data
|
|
* may have been left unvacuumed, so we can't update XID stats.)
|
|
*
|
|
* Doing one heap at a time incurs extra overhead, since we need to
|
|
* check that the heap exists again just before we vacuum it. The
|
|
* reason that we do this is so that vacuuming can be spread across
|
|
* many small transactions. Otherwise, two-phase locking would require
|
|
* us to lock the entire database during one pass of the vacuum cleaner.
|
|
*
|
|
* At entry and exit, we are not inside a transaction.
|
|
*/
|
|
static bool
|
|
vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
|
|
{
|
|
LOCKMODE lmode;
|
|
Relation onerel;
|
|
LockRelId onerelid;
|
|
Oid toast_relid;
|
|
bool result;
|
|
|
|
/* Begin a transaction for vacuuming this relation */
|
|
StartTransactionCommand();
|
|
/* functions in indexes may want a snapshot set */
|
|
ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
|
|
|
|
/*
|
|
* Tell the cache replacement strategy that vacuum is causing all
|
|
* following IO
|
|
*/
|
|
StrategyHintVacuum(true);
|
|
|
|
/*
|
|
* Check for user-requested abort. Note we want this to be inside a
|
|
* transaction, so xact.c doesn't issue useless WARNING.
|
|
*/
|
|
CHECK_FOR_INTERRUPTS();
|
|
|
|
/*
|
|
* Race condition -- if the pg_class tuple has gone away since the
|
|
* last time we saw it, we don't need to vacuum it.
|
|
*/
|
|
if (!SearchSysCacheExists(RELOID,
|
|
ObjectIdGetDatum(relid),
|
|
0, 0, 0))
|
|
{
|
|
StrategyHintVacuum(false);
|
|
CommitTransactionCommand();
|
|
return true; /* okay 'cause no data there */
|
|
}
|
|
|
|
/*
|
|
* Determine the type of lock we want --- hard exclusive lock for a
|
|
* FULL vacuum, but just ShareUpdateExclusiveLock for concurrent
|
|
* vacuum. Either way, we can be sure that no other backend is
|
|
* vacuuming the same table.
|
|
*/
|
|
lmode = vacstmt->full ? AccessExclusiveLock : ShareUpdateExclusiveLock;
|
|
|
|
/*
|
|
* Open the class, get an appropriate lock on it, and check
|
|
* permissions.
|
|
*
|
|
* We allow the user to vacuum a table if he is superuser, the table
|
|
* owner, or the database owner (but in the latter case, only if it's
|
|
* not a shared relation). pg_class_ownercheck includes the superuser
|
|
* case.
|
|
*
|
|
* Note we choose to treat permissions failure as a WARNING and keep
|
|
* trying to vacuum the rest of the DB --- is this appropriate?
|
|
*/
|
|
onerel = relation_open(relid, lmode);
|
|
|
|
if (!(pg_class_ownercheck(RelationGetRelid(onerel), GetUserId()) ||
|
|
(pg_database_ownercheck(MyDatabaseId, GetUserId()) && !onerel->rd_rel->relisshared)))
|
|
{
|
|
ereport(WARNING,
|
|
(errmsg("skipping \"%s\" --- only table or database owner can vacuum it",
|
|
RelationGetRelationName(onerel))));
|
|
relation_close(onerel, lmode);
|
|
StrategyHintVacuum(false);
|
|
CommitTransactionCommand();
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Check that it's a plain table; we used to do this in get_rel_oids()
|
|
* but seems safer to check after we've locked the relation.
|
|
*/
|
|
if (onerel->rd_rel->relkind != expected_relkind)
|
|
{
|
|
ereport(WARNING,
|
|
(errmsg("skipping \"%s\" --- cannot vacuum indexes, views, or special system tables",
|
|
RelationGetRelationName(onerel))));
|
|
relation_close(onerel, lmode);
|
|
StrategyHintVacuum(false);
|
|
CommitTransactionCommand();
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Silently ignore tables that are temp tables of other backends ---
|
|
* trying to vacuum these will lead to great unhappiness, since their
|
|
* contents are probably not up-to-date on disk. (We don't throw a
|
|
* warning here; it would just lead to chatter during a database-wide
|
|
* VACUUM.)
|
|
*/
|
|
if (isOtherTempNamespace(RelationGetNamespace(onerel)))
|
|
{
|
|
relation_close(onerel, lmode);
|
|
StrategyHintVacuum(false);
|
|
CommitTransactionCommand();
|
|
return true; /* assume no long-lived data in temp
|
|
* tables */
|
|
}
|
|
|
|
/*
|
|
* Get a session-level lock too. This will protect our access to the
|
|
* relation across multiple transactions, so that we can vacuum the
|
|
* relation's TOAST table (if any) secure in the knowledge that no one
|
|
* is deleting the parent relation.
|
|
*
|
|
* NOTE: this cannot block, even if someone else is waiting for access,
|
|
* because the lock manager knows that both lock requests are from the
|
|
* same process.
|
|
*/
|
|
onerelid = onerel->rd_lockInfo.lockRelId;
|
|
LockRelationForSession(&onerelid, onerel->rd_istemp, lmode);
|
|
|
|
/*
|
|
* Remember the relation's TOAST relation for later
|
|
*/
|
|
toast_relid = onerel->rd_rel->reltoastrelid;
|
|
|
|
/*
|
|
* Do the actual work --- either FULL or "lazy" vacuum
|
|
*/
|
|
if (vacstmt->full)
|
|
full_vacuum_rel(onerel, vacstmt);
|
|
else
|
|
lazy_vacuum_rel(onerel, vacstmt);
|
|
|
|
result = true; /* did the vacuum */
|
|
|
|
/* all done with this class, but hold lock until commit */
|
|
relation_close(onerel, NoLock);
|
|
|
|
/*
|
|
* Complete the transaction and free all temporary memory used.
|
|
*/
|
|
StrategyHintVacuum(false);
|
|
CommitTransactionCommand();
|
|
|
|
/*
|
|
* If the relation has a secondary toast rel, vacuum that too while we
|
|
* still hold the session lock on the master table. Note however that
|
|
* "analyze" will not get done on the toast table. This is good,
|
|
* because the toaster always uses hardcoded index access and
|
|
* statistics are totally unimportant for toast relations.
|
|
*/
|
|
if (toast_relid != InvalidOid)
|
|
{
|
|
if (!vacuum_rel(toast_relid, vacstmt, RELKIND_TOASTVALUE))
|
|
result = false; /* failed to vacuum the TOAST table? */
|
|
}
|
|
|
|
/*
|
|
* Now release the session-level lock on the master table.
|
|
*/
|
|
UnlockRelationForSession(&onerelid, lmode);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/****************************************************************************
|
|
* *
|
|
* Code for VACUUM FULL (only) *
|
|
* *
|
|
****************************************************************************
|
|
*/
|
|
|
|
|
|
/*
|
|
* full_vacuum_rel() -- perform FULL VACUUM for one heap relation
|
|
*
|
|
* This routine vacuums a single heap, cleans out its indexes, and
|
|
* updates its num_pages and num_tuples statistics.
|
|
*
|
|
* At entry, we have already established a transaction and opened
|
|
* and locked the relation.
|
|
*/
|
|
static void
|
|
full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt)
|
|
{
|
|
VacPageListData vacuum_pages; /* List of pages to vacuum and/or
|
|
* clean indexes */
|
|
VacPageListData fraged_pages; /* List of pages with space enough
|
|
* for re-using */
|
|
Relation *Irel;
|
|
int nindexes,
|
|
i;
|
|
VRelStats *vacrelstats;
|
|
|
|
vacuum_set_xid_limits(vacstmt, onerel->rd_rel->relisshared,
|
|
&OldestXmin, &FreezeLimit);
|
|
|
|
/*
|
|
* Set up statistics-gathering machinery.
|
|
*/
|
|
vacrelstats = (VRelStats *) palloc(sizeof(VRelStats));
|
|
vacrelstats->rel_pages = 0;
|
|
vacrelstats->rel_tuples = 0;
|
|
vacrelstats->hasindex = false;
|
|
|
|
/* scan the heap */
|
|
vacuum_pages.num_pages = fraged_pages.num_pages = 0;
|
|
scan_heap(vacrelstats, onerel, &vacuum_pages, &fraged_pages);
|
|
|
|
/* Now open all indexes of the relation */
|
|
vac_open_indexes(onerel, AccessExclusiveLock, &nindexes, &Irel);
|
|
if (nindexes > 0)
|
|
vacrelstats->hasindex = true;
|
|
|
|
/* Clean/scan index relation(s) */
|
|
if (Irel != NULL)
|
|
{
|
|
if (vacuum_pages.num_pages > 0)
|
|
{
|
|
for (i = 0; i < nindexes; i++)
|
|
vacuum_index(&vacuum_pages, Irel[i],
|
|
vacrelstats->rel_tuples, 0);
|
|
}
|
|
else
|
|
{
|
|
/* just scan indexes to update statistic */
|
|
for (i = 0; i < nindexes; i++)
|
|
scan_index(Irel[i], vacrelstats->rel_tuples);
|
|
}
|
|
}
|
|
|
|
if (fraged_pages.num_pages > 0)
|
|
{
|
|
/* Try to shrink heap */
|
|
repair_frag(vacrelstats, onerel, &vacuum_pages, &fraged_pages,
|
|
nindexes, Irel);
|
|
vac_close_indexes(nindexes, Irel, NoLock);
|
|
}
|
|
else
|
|
{
|
|
vac_close_indexes(nindexes, Irel, NoLock);
|
|
if (vacuum_pages.num_pages > 0)
|
|
{
|
|
/* Clean pages from vacuum_pages list */
|
|
vacuum_heap(vacrelstats, onerel, &vacuum_pages);
|
|
}
|
|
}
|
|
|
|
/* update shared free space map with final free space info */
|
|
vac_update_fsm(onerel, &fraged_pages, vacrelstats->rel_pages);
|
|
|
|
/* update statistics in pg_class */
|
|
vac_update_relstats(RelationGetRelid(onerel), vacrelstats->rel_pages,
|
|
vacrelstats->rel_tuples, vacrelstats->hasindex);
|
|
}
|
|
|
|
|
|
/*
|
|
* scan_heap() -- scan an open heap relation
|
|
*
|
|
* This routine sets commit status bits, constructs vacuum_pages (list
|
|
* of pages we need to compact free space on and/or clean indexes of
|
|
* deleted tuples), constructs fraged_pages (list of pages with free
|
|
* space that tuples could be moved into), and calculates statistics
|
|
* on the number of live tuples in the heap.
|
|
*/
|
|
static void
|
|
scan_heap(VRelStats *vacrelstats, Relation onerel,
|
|
VacPageList vacuum_pages, VacPageList fraged_pages)
|
|
{
|
|
BlockNumber nblocks,
|
|
blkno;
|
|
HeapTupleData tuple;
|
|
char *relname;
|
|
VacPage vacpage;
|
|
BlockNumber empty_pages,
|
|
empty_end_pages;
|
|
double num_tuples,
|
|
tups_vacuumed,
|
|
nkeep,
|
|
nunused;
|
|
double free_space,
|
|
usable_free_space;
|
|
Size min_tlen = MaxTupleSize;
|
|
Size max_tlen = 0;
|
|
bool do_shrinking = true;
|
|
VTupleLink vtlinks = (VTupleLink) palloc(100 * sizeof(VTupleLinkData));
|
|
int num_vtlinks = 0;
|
|
int free_vtlinks = 100;
|
|
VacRUsage ru0;
|
|
|
|
vac_init_rusage(&ru0);
|
|
|
|
relname = RelationGetRelationName(onerel);
|
|
ereport(elevel,
|
|
(errmsg("vacuuming \"%s.%s\"",
|
|
get_namespace_name(RelationGetNamespace(onerel)),
|
|
relname)));
|
|
|
|
empty_pages = empty_end_pages = 0;
|
|
num_tuples = tups_vacuumed = nkeep = nunused = 0;
|
|
free_space = 0;
|
|
|
|
nblocks = RelationGetNumberOfBlocks(onerel);
|
|
|
|
/*
|
|
* We initially create each VacPage item in a maximal-sized workspace,
|
|
* then copy the workspace into a just-large-enough copy.
|
|
*/
|
|
vacpage = (VacPage) palloc(sizeof(VacPageData) + MaxOffsetNumber * sizeof(OffsetNumber));
|
|
|
|
for (blkno = 0; blkno < nblocks; blkno++)
|
|
{
|
|
Page page,
|
|
tempPage = NULL;
|
|
bool do_reap,
|
|
do_frag;
|
|
Buffer buf;
|
|
OffsetNumber offnum,
|
|
maxoff;
|
|
bool pgchanged,
|
|
notup;
|
|
|
|
vacuum_delay_point();
|
|
|
|
buf = ReadBuffer(onerel, blkno);
|
|
page = BufferGetPage(buf);
|
|
|
|
/*
|
|
* We don't bother to do LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE)
|
|
* because we assume that holding exclusive lock on the relation
|
|
* will keep other backends from looking at the page.
|
|
*/
|
|
|
|
vacpage->blkno = blkno;
|
|
vacpage->offsets_used = 0;
|
|
vacpage->offsets_free = 0;
|
|
|
|
if (PageIsNew(page))
|
|
{
|
|
VacPage vacpagecopy;
|
|
|
|
ereport(WARNING,
|
|
(errmsg("relation \"%s\" page %u is uninitialized --- fixing",
|
|
relname, blkno)));
|
|
PageInit(page, BufferGetPageSize(buf), 0);
|
|
vacpage->free = ((PageHeader) page)->pd_upper - ((PageHeader) page)->pd_lower;
|
|
free_space += vacpage->free;
|
|
empty_pages++;
|
|
empty_end_pages++;
|
|
vacpagecopy = copy_vac_page(vacpage);
|
|
vpage_insert(vacuum_pages, vacpagecopy);
|
|
vpage_insert(fraged_pages, vacpagecopy);
|
|
WriteBuffer(buf);
|
|
continue;
|
|
}
|
|
|
|
if (PageIsEmpty(page))
|
|
{
|
|
VacPage vacpagecopy;
|
|
|
|
vacpage->free = ((PageHeader) page)->pd_upper - ((PageHeader) page)->pd_lower;
|
|
free_space += vacpage->free;
|
|
empty_pages++;
|
|
empty_end_pages++;
|
|
vacpagecopy = copy_vac_page(vacpage);
|
|
vpage_insert(vacuum_pages, vacpagecopy);
|
|
vpage_insert(fraged_pages, vacpagecopy);
|
|
ReleaseBuffer(buf);
|
|
continue;
|
|
}
|
|
|
|
pgchanged = false;
|
|
notup = true;
|
|
maxoff = PageGetMaxOffsetNumber(page);
|
|
for (offnum = FirstOffsetNumber;
|
|
offnum <= maxoff;
|
|
offnum = OffsetNumberNext(offnum))
|
|
{
|
|
ItemId itemid = PageGetItemId(page, offnum);
|
|
bool tupgone = false;
|
|
|
|
/*
|
|
* Collect un-used items too - it's possible to have indexes
|
|
* pointing here after crash.
|
|
*/
|
|
if (!ItemIdIsUsed(itemid))
|
|
{
|
|
vacpage->offsets[vacpage->offsets_free++] = offnum;
|
|
nunused += 1;
|
|
continue;
|
|
}
|
|
|
|
tuple.t_datamcxt = NULL;
|
|
tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
|
|
tuple.t_len = ItemIdGetLength(itemid);
|
|
ItemPointerSet(&(tuple.t_self), blkno, offnum);
|
|
|
|
switch (HeapTupleSatisfiesVacuum(tuple.t_data, OldestXmin, buf))
|
|
{
|
|
case HEAPTUPLE_DEAD:
|
|
tupgone = true; /* we can delete the tuple */
|
|
break;
|
|
case HEAPTUPLE_LIVE:
|
|
|
|
/*
|
|
* Tuple is good. Consider whether to replace its
|
|
* xmin value with FrozenTransactionId.
|
|
*/
|
|
if (TransactionIdIsNormal(HeapTupleHeaderGetXmin(tuple.t_data)) &&
|
|
TransactionIdPrecedes(HeapTupleHeaderGetXmin(tuple.t_data),
|
|
FreezeLimit))
|
|
{
|
|
HeapTupleHeaderSetXmin(tuple.t_data, FrozenTransactionId);
|
|
/* infomask should be okay already */
|
|
Assert(tuple.t_data->t_infomask & HEAP_XMIN_COMMITTED);
|
|
pgchanged = true;
|
|
}
|
|
|
|
/*
|
|
* Other checks...
|
|
*/
|
|
if (onerel->rd_rel->relhasoids &&
|
|
!OidIsValid(HeapTupleGetOid(&tuple)))
|
|
elog(WARNING, "relation \"%s\" TID %u/%u: OID is invalid",
|
|
relname, blkno, offnum);
|
|
break;
|
|
case HEAPTUPLE_RECENTLY_DEAD:
|
|
|
|
/*
|
|
* If tuple is recently deleted then we must not
|
|
* remove it from relation.
|
|
*/
|
|
nkeep += 1;
|
|
|
|
/*
|
|
* If we do shrinking and this tuple is updated one
|
|
* then remember it to construct updated tuple
|
|
* dependencies.
|
|
*/
|
|
if (do_shrinking &&
|
|
!(ItemPointerEquals(&(tuple.t_self),
|
|
&(tuple.t_data->t_ctid))))
|
|
{
|
|
if (free_vtlinks == 0)
|
|
{
|
|
free_vtlinks = 1000;
|
|
vtlinks = (VTupleLink) repalloc(vtlinks,
|
|
(free_vtlinks + num_vtlinks) *
|
|
sizeof(VTupleLinkData));
|
|
}
|
|
vtlinks[num_vtlinks].new_tid = tuple.t_data->t_ctid;
|
|
vtlinks[num_vtlinks].this_tid = tuple.t_self;
|
|
free_vtlinks--;
|
|
num_vtlinks++;
|
|
}
|
|
break;
|
|
case HEAPTUPLE_INSERT_IN_PROGRESS:
|
|
|
|
/*
|
|
* This should not happen, since we hold exclusive
|
|
* lock on the relation; shouldn't we raise an error?
|
|
* (Actually, it can happen in system catalogs, since
|
|
* we tend to release write lock before commit there.)
|
|
*/
|
|
ereport(NOTICE,
|
|
(errmsg("relation \"%s\" TID %u/%u: InsertTransactionInProgress %u --- can't shrink relation",
|
|
relname, blkno, offnum, HeapTupleHeaderGetXmin(tuple.t_data))));
|
|
do_shrinking = false;
|
|
break;
|
|
case HEAPTUPLE_DELETE_IN_PROGRESS:
|
|
|
|
/*
|
|
* This should not happen, since we hold exclusive
|
|
* lock on the relation; shouldn't we raise an error?
|
|
* (Actually, it can happen in system catalogs, since
|
|
* we tend to release write lock before commit there.)
|
|
*/
|
|
ereport(NOTICE,
|
|
(errmsg("relation \"%s\" TID %u/%u: DeleteTransactionInProgress %u --- can't shrink relation",
|
|
relname, blkno, offnum, HeapTupleHeaderGetXmax(tuple.t_data))));
|
|
do_shrinking = false;
|
|
break;
|
|
default:
|
|
elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
|
|
break;
|
|
}
|
|
|
|
if (tupgone)
|
|
{
|
|
ItemId lpp;
|
|
|
|
/*
|
|
* Here we are building a temporary copy of the page with
|
|
* dead tuples removed. Below we will apply
|
|
* PageRepairFragmentation to the copy, so that we can
|
|
* determine how much space will be available after
|
|
* removal of dead tuples. But note we are NOT changing
|
|
* the real page yet...
|
|
*/
|
|
if (tempPage == NULL)
|
|
{
|
|
Size pageSize;
|
|
|
|
pageSize = PageGetPageSize(page);
|
|
tempPage = (Page) palloc(pageSize);
|
|
memcpy(tempPage, page, pageSize);
|
|
}
|
|
|
|
/* mark it unused on the temp page */
|
|
lpp = PageGetItemId(tempPage, offnum);
|
|
lpp->lp_flags &= ~LP_USED;
|
|
|
|
vacpage->offsets[vacpage->offsets_free++] = offnum;
|
|
tups_vacuumed += 1;
|
|
}
|
|
else
|
|
{
|
|
num_tuples += 1;
|
|
notup = false;
|
|
if (tuple.t_len < min_tlen)
|
|
min_tlen = tuple.t_len;
|
|
if (tuple.t_len > max_tlen)
|
|
max_tlen = tuple.t_len;
|
|
}
|
|
} /* scan along page */
|
|
|
|
if (tempPage != NULL)
|
|
{
|
|
/* Some tuples are removable; figure free space after removal */
|
|
PageRepairFragmentation(tempPage, NULL);
|
|
vacpage->free = ((PageHeader) tempPage)->pd_upper - ((PageHeader) tempPage)->pd_lower;
|
|
pfree(tempPage);
|
|
do_reap = true;
|
|
}
|
|
else
|
|
{
|
|
/* Just use current available space */
|
|
vacpage->free = ((PageHeader) page)->pd_upper - ((PageHeader) page)->pd_lower;
|
|
/* Need to reap the page if it has ~LP_USED line pointers */
|
|
do_reap = (vacpage->offsets_free > 0);
|
|
}
|
|
|
|
free_space += vacpage->free;
|
|
|
|
/*
|
|
* Add the page to fraged_pages if it has a useful amount of free
|
|
* space. "Useful" means enough for a minimal-sized tuple. But we
|
|
* don't know that accurately near the start of the relation, so
|
|
* add pages unconditionally if they have >= BLCKSZ/10 free space.
|
|
*/
|
|
do_frag = (vacpage->free >= min_tlen || vacpage->free >= BLCKSZ / 10);
|
|
|
|
if (do_reap || do_frag)
|
|
{
|
|
VacPage vacpagecopy = copy_vac_page(vacpage);
|
|
|
|
if (do_reap)
|
|
vpage_insert(vacuum_pages, vacpagecopy);
|
|
if (do_frag)
|
|
vpage_insert(fraged_pages, vacpagecopy);
|
|
}
|
|
|
|
/*
|
|
* Include the page in empty_end_pages if it will be empty after
|
|
* vacuuming; this is to keep us from using it as a move
|
|
* destination.
|
|
*/
|
|
if (notup)
|
|
{
|
|
empty_pages++;
|
|
empty_end_pages++;
|
|
}
|
|
else
|
|
empty_end_pages = 0;
|
|
|
|
if (pgchanged)
|
|
WriteBuffer(buf);
|
|
else
|
|
ReleaseBuffer(buf);
|
|
}
|
|
|
|
pfree(vacpage);
|
|
|
|
/* save stats in the rel list for use later */
|
|
vacrelstats->rel_tuples = num_tuples;
|
|
vacrelstats->rel_pages = nblocks;
|
|
if (num_tuples == 0)
|
|
min_tlen = max_tlen = 0;
|
|
vacrelstats->min_tlen = min_tlen;
|
|
vacrelstats->max_tlen = max_tlen;
|
|
|
|
vacuum_pages->empty_end_pages = empty_end_pages;
|
|
fraged_pages->empty_end_pages = empty_end_pages;
|
|
|
|
/*
|
|
* Clear the fraged_pages list if we found we couldn't shrink. Else,
|
|
* remove any "empty" end-pages from the list, and compute usable free
|
|
* space = free space in remaining pages.
|
|
*/
|
|
if (do_shrinking)
|
|
{
|
|
int i;
|
|
|
|
Assert((BlockNumber) fraged_pages->num_pages >= empty_end_pages);
|
|
fraged_pages->num_pages -= empty_end_pages;
|
|
usable_free_space = 0;
|
|
for (i = 0; i < fraged_pages->num_pages; i++)
|
|
usable_free_space += fraged_pages->pagedesc[i]->free;
|
|
}
|
|
else
|
|
{
|
|
fraged_pages->num_pages = 0;
|
|
usable_free_space = 0;
|
|
}
|
|
|
|
/* don't bother to save vtlinks if we will not call repair_frag */
|
|
if (fraged_pages->num_pages > 0 && num_vtlinks > 0)
|
|
{
|
|
qsort((char *) vtlinks, num_vtlinks, sizeof(VTupleLinkData),
|
|
vac_cmp_vtlinks);
|
|
vacrelstats->vtlinks = vtlinks;
|
|
vacrelstats->num_vtlinks = num_vtlinks;
|
|
}
|
|
else
|
|
{
|
|
vacrelstats->vtlinks = NULL;
|
|
vacrelstats->num_vtlinks = 0;
|
|
pfree(vtlinks);
|
|
}
|
|
|
|
ereport(elevel,
|
|
(errmsg("\"%s\": found %.0f removable, %.0f nonremovable row versions in %u pages",
|
|
RelationGetRelationName(onerel),
|
|
tups_vacuumed, num_tuples, nblocks),
|
|
errdetail("%.0f dead row versions cannot be removed yet.\n"
|
|
"Nonremovable row versions range from %lu to %lu bytes long.\n"
|
|
"There were %.0f unused item pointers.\n"
|
|
"Total free space (including removable row versions) is %.0f bytes.\n"
|
|
"%u pages are or will become empty, including %u at the end of the table.\n"
|
|
"%u pages containing %.0f free bytes are potential move destinations.\n"
|
|
"%s",
|
|
nkeep,
|
|
(unsigned long) min_tlen, (unsigned long) max_tlen,
|
|
nunused,
|
|
free_space,
|
|
empty_pages, empty_end_pages,
|
|
fraged_pages->num_pages, usable_free_space,
|
|
vac_show_rusage(&ru0))));
|
|
}
|
|
|
|
|
|
/*
|
|
* repair_frag() -- try to repair relation's fragmentation
|
|
*
|
|
* This routine marks dead tuples as unused and tries re-use dead space
|
|
* by moving tuples (and inserting indexes if needed). It constructs
|
|
* Nvacpagelist list of free-ed pages (moved tuples) and clean indexes
|
|
* for them after committing (in hack-manner - without losing locks
|
|
* and freeing memory!) current transaction. It truncates relation
|
|
* if some end-blocks are gone away.
|
|
*/
|
|
static void
|
|
repair_frag(VRelStats *vacrelstats, Relation onerel,
|
|
VacPageList vacuum_pages, VacPageList fraged_pages,
|
|
int nindexes, Relation *Irel)
|
|
{
|
|
TransactionId myXID = GetCurrentTransactionId();
|
|
Buffer dst_buffer = InvalidBuffer;
|
|
BlockNumber nblocks,
|
|
blkno;
|
|
BlockNumber last_move_dest_block = 0,
|
|
last_vacuum_block;
|
|
Page dst_page = NULL;
|
|
ExecContextData ec;
|
|
VacPageListData Nvacpagelist;
|
|
VacPage dst_vacpage = NULL,
|
|
last_vacuum_page,
|
|
vacpage,
|
|
*curpage;
|
|
int i;
|
|
int num_moved = 0,
|
|
num_fraged_pages,
|
|
vacuumed_pages;
|
|
int keep_tuples = 0;
|
|
VacRUsage ru0;
|
|
|
|
vac_init_rusage(&ru0);
|
|
|
|
ExecContext_Init(&ec, onerel);
|
|
|
|
Nvacpagelist.num_pages = 0;
|
|
num_fraged_pages = fraged_pages->num_pages;
|
|
Assert((BlockNumber) vacuum_pages->num_pages >= vacuum_pages->empty_end_pages);
|
|
vacuumed_pages = vacuum_pages->num_pages - vacuum_pages->empty_end_pages;
|
|
if (vacuumed_pages > 0)
|
|
{
|
|
/* get last reaped page from vacuum_pages */
|
|
last_vacuum_page = vacuum_pages->pagedesc[vacuumed_pages - 1];
|
|
last_vacuum_block = last_vacuum_page->blkno;
|
|
}
|
|
else
|
|
{
|
|
last_vacuum_page = NULL;
|
|
last_vacuum_block = InvalidBlockNumber;
|
|
}
|
|
|
|
vacpage = (VacPage) palloc(sizeof(VacPageData) + MaxOffsetNumber * sizeof(OffsetNumber));
|
|
vacpage->offsets_used = vacpage->offsets_free = 0;
|
|
|
|
/*
|
|
* Scan pages backwards from the last nonempty page, trying to move
|
|
* tuples down to lower pages. Quit when we reach a page that we have
|
|
* moved any tuples onto, or the first page if we haven't moved
|
|
* anything, or when we find a page we cannot completely empty (this
|
|
* last condition is handled by "break" statements within the loop).
|
|
*
|
|
* NB: this code depends on the vacuum_pages and fraged_pages lists being
|
|
* in order by blkno.
|
|
*/
|
|
nblocks = vacrelstats->rel_pages;
|
|
for (blkno = nblocks - vacuum_pages->empty_end_pages - 1;
|
|
blkno > last_move_dest_block;
|
|
blkno--)
|
|
{
|
|
Buffer buf;
|
|
Page page;
|
|
OffsetNumber offnum,
|
|
maxoff;
|
|
bool isempty,
|
|
dowrite,
|
|
chain_tuple_moved;
|
|
|
|
vacuum_delay_point();
|
|
|
|
/*
|
|
* Forget fraged_pages pages at or after this one; they're no
|
|
* longer useful as move targets, since we only want to move down.
|
|
* Note that since we stop the outer loop at last_move_dest_block,
|
|
* pages removed here cannot have had anything moved onto them
|
|
* already.
|
|
*
|
|
* Also note that we don't change the stored fraged_pages list, only
|
|
* our local variable num_fraged_pages; so the forgotten pages are
|
|
* still available to be loaded into the free space map later.
|
|
*/
|
|
while (num_fraged_pages > 0 &&
|
|
fraged_pages->pagedesc[num_fraged_pages - 1]->blkno >= blkno)
|
|
{
|
|
Assert(fraged_pages->pagedesc[num_fraged_pages - 1]->offsets_used == 0);
|
|
--num_fraged_pages;
|
|
}
|
|
|
|
/*
|
|
* Process this page of relation.
|
|
*/
|
|
buf = ReadBuffer(onerel, blkno);
|
|
page = BufferGetPage(buf);
|
|
|
|
vacpage->offsets_free = 0;
|
|
|
|
isempty = PageIsEmpty(page);
|
|
|
|
dowrite = false;
|
|
|
|
/* Is the page in the vacuum_pages list? */
|
|
if (blkno == last_vacuum_block)
|
|
{
|
|
if (last_vacuum_page->offsets_free > 0)
|
|
{
|
|
/* there are dead tuples on this page - clean them */
|
|
Assert(!isempty);
|
|
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
|
|
vacuum_page(onerel, buf, last_vacuum_page);
|
|
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
|
|
dowrite = true;
|
|
}
|
|
else
|
|
Assert(isempty);
|
|
--vacuumed_pages;
|
|
if (vacuumed_pages > 0)
|
|
{
|
|
/* get prev reaped page from vacuum_pages */
|
|
last_vacuum_page = vacuum_pages->pagedesc[vacuumed_pages - 1];
|
|
last_vacuum_block = last_vacuum_page->blkno;
|
|
}
|
|
else
|
|
{
|
|
last_vacuum_page = NULL;
|
|
last_vacuum_block = InvalidBlockNumber;
|
|
}
|
|
if (isempty)
|
|
{
|
|
ReleaseBuffer(buf);
|
|
continue;
|
|
}
|
|
}
|
|
else
|
|
Assert(!isempty);
|
|
|
|
chain_tuple_moved = false; /* no one chain-tuple was moved
|
|
* off this page, yet */
|
|
vacpage->blkno = blkno;
|
|
maxoff = PageGetMaxOffsetNumber(page);
|
|
for (offnum = FirstOffsetNumber;
|
|
offnum <= maxoff;
|
|
offnum = OffsetNumberNext(offnum))
|
|
{
|
|
Size tuple_len;
|
|
HeapTupleData tuple;
|
|
ItemId itemid = PageGetItemId(page, offnum);
|
|
|
|
if (!ItemIdIsUsed(itemid))
|
|
continue;
|
|
|
|
tuple.t_datamcxt = NULL;
|
|
tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
|
|
tuple_len = tuple.t_len = ItemIdGetLength(itemid);
|
|
ItemPointerSet(&(tuple.t_self), blkno, offnum);
|
|
|
|
/* ---
|
|
* VACUUM FULL has an exclusive lock on the relation. So
|
|
* normally no other transaction can have pending INSERTs or
|
|
* DELETEs in this relation. A tuple is either:
|
|
* (a) a tuple in a system catalog, inserted or deleted
|
|
* by a not yet committed transaction
|
|
* (b) known dead (XMIN_INVALID, or XMAX_COMMITTED and xmax
|
|
* is visible to all active transactions)
|
|
* (c) inserted by a committed xact (XMIN_COMMITTED)
|
|
* (d) moved by the currently running VACUUM.
|
|
* (e) deleted (XMAX_COMMITTED) but at least one active
|
|
* transaction does not see the deleting transaction
|
|
* In case (a) we wouldn't be in repair_frag() at all.
|
|
* In case (b) we cannot be here, because scan_heap() has
|
|
* already marked the item as unused, see continue above. Case
|
|
* (c) is what normally is to be expected. Case (d) is only
|
|
* possible, if a whole tuple chain has been moved while
|
|
* processing this or a higher numbered block.
|
|
* ---
|
|
*/
|
|
if (!(tuple.t_data->t_infomask & HEAP_XMIN_COMMITTED))
|
|
{
|
|
if (tuple.t_data->t_infomask & HEAP_MOVED_IN)
|
|
elog(ERROR, "HEAP_MOVED_IN was not expected");
|
|
if (!(tuple.t_data->t_infomask & HEAP_MOVED_OFF))
|
|
elog(ERROR, "HEAP_MOVED_OFF was expected");
|
|
|
|
/*
|
|
* MOVED_OFF by another VACUUM would have caused the
|
|
* visibility check to set XMIN_COMMITTED or XMIN_INVALID.
|
|
*/
|
|
if (HeapTupleHeaderGetXvac(tuple.t_data) != myXID)
|
|
elog(ERROR, "invalid XVAC in tuple header");
|
|
|
|
/*
|
|
* If this (chain) tuple is moved by me already then I
|
|
* have to check is it in vacpage or not - i.e. is it
|
|
* moved while cleaning this page or some previous one.
|
|
*/
|
|
|
|
/* Can't we Assert(keep_tuples > 0) here? */
|
|
if (keep_tuples == 0)
|
|
continue;
|
|
if (chain_tuple_moved)
|
|
{
|
|
/* some chains were moved while cleaning this page */
|
|
Assert(vacpage->offsets_free > 0);
|
|
for (i = 0; i < vacpage->offsets_free; i++)
|
|
{
|
|
if (vacpage->offsets[i] == offnum)
|
|
break;
|
|
}
|
|
if (i >= vacpage->offsets_free) /* not found */
|
|
{
|
|
vacpage->offsets[vacpage->offsets_free++] = offnum;
|
|
keep_tuples--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
vacpage->offsets[vacpage->offsets_free++] = offnum;
|
|
keep_tuples--;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* If this tuple is in the chain of tuples created in updates
|
|
* by "recent" transactions then we have to move all chain of
|
|
* tuples to another places.
|
|
*
|
|
* NOTE: this test is not 100% accurate: it is possible for a
|
|
* tuple to be an updated one with recent xmin, and yet not
|
|
* have a corresponding tuple in the vtlinks list. Presumably
|
|
* there was once a parent tuple with xmax matching the xmin,
|
|
* but it's possible that that tuple has been removed --- for
|
|
* example, if it had xmin = xmax then
|
|
* HeapTupleSatisfiesVacuum would deem it removable as soon as
|
|
* the xmin xact completes.
|
|
*
|
|
* To be on the safe side, we abandon the repair_frag process if
|
|
* we cannot find the parent tuple in vtlinks. This may be
|
|
* overly conservative; AFAICS it would be safe to move the
|
|
* chain.
|
|
*/
|
|
if (((tuple.t_data->t_infomask & HEAP_UPDATED) &&
|
|
!TransactionIdPrecedes(HeapTupleHeaderGetXmin(tuple.t_data),
|
|
OldestXmin)) ||
|
|
(!(tuple.t_data->t_infomask & (HEAP_XMAX_INVALID |
|
|
HEAP_IS_LOCKED)) &&
|
|
!(ItemPointerEquals(&(tuple.t_self),
|
|
&(tuple.t_data->t_ctid)))))
|
|
{
|
|
Buffer Cbuf = buf;
|
|
bool freeCbuf = false;
|
|
bool chain_move_failed = false;
|
|
ItemPointerData Ctid;
|
|
HeapTupleData tp = tuple;
|
|
Size tlen = tuple_len;
|
|
VTupleMove vtmove;
|
|
int num_vtmove;
|
|
int free_vtmove;
|
|
VacPage to_vacpage = NULL;
|
|
int to_item = 0;
|
|
int ti;
|
|
|
|
if (dst_buffer != InvalidBuffer)
|
|
{
|
|
WriteBuffer(dst_buffer);
|
|
dst_buffer = InvalidBuffer;
|
|
}
|
|
|
|
/* Quick exit if we have no vtlinks to search in */
|
|
if (vacrelstats->vtlinks == NULL)
|
|
{
|
|
elog(DEBUG2, "parent item in update-chain not found --- can't continue repair_frag");
|
|
break; /* out of walk-along-page loop */
|
|
}
|
|
|
|
vtmove = (VTupleMove) palloc(100 * sizeof(VTupleMoveData));
|
|
num_vtmove = 0;
|
|
free_vtmove = 100;
|
|
|
|
/*
|
|
* If this tuple is in the begin/middle of the chain then
|
|
* we have to move to the end of chain.
|
|
*/
|
|
while (!(tp.t_data->t_infomask & (HEAP_XMAX_INVALID |
|
|
HEAP_IS_LOCKED)) &&
|
|
!(ItemPointerEquals(&(tp.t_self),
|
|
&(tp.t_data->t_ctid))))
|
|
{
|
|
Page Cpage;
|
|
ItemId Citemid;
|
|
ItemPointerData Ctid;
|
|
|
|
Ctid = tp.t_data->t_ctid;
|
|
if (freeCbuf)
|
|
ReleaseBuffer(Cbuf);
|
|
freeCbuf = true;
|
|
Cbuf = ReadBuffer(onerel,
|
|
ItemPointerGetBlockNumber(&Ctid));
|
|
Cpage = BufferGetPage(Cbuf);
|
|
Citemid = PageGetItemId(Cpage,
|
|
ItemPointerGetOffsetNumber(&Ctid));
|
|
if (!ItemIdIsUsed(Citemid))
|
|
{
|
|
/*
|
|
* This means that in the middle of chain there
|
|
* was tuple updated by older (than OldestXmin)
|
|
* xaction and this tuple is already deleted by
|
|
* me. Actually, upper part of chain should be
|
|
* removed and seems that this should be handled
|
|
* in scan_heap(), but it's not implemented at the
|
|
* moment and so we just stop shrinking here.
|
|
*/
|
|
elog(DEBUG2, "child itemid in update-chain marked as unused --- can't continue repair_frag");
|
|
chain_move_failed = true;
|
|
break; /* out of loop to move to chain end */
|
|
}
|
|
tp.t_datamcxt = NULL;
|
|
tp.t_data = (HeapTupleHeader) PageGetItem(Cpage, Citemid);
|
|
tp.t_self = Ctid;
|
|
tlen = tp.t_len = ItemIdGetLength(Citemid);
|
|
}
|
|
if (chain_move_failed)
|
|
{
|
|
if (freeCbuf)
|
|
ReleaseBuffer(Cbuf);
|
|
pfree(vtmove);
|
|
break; /* out of walk-along-page loop */
|
|
}
|
|
|
|
/*
|
|
* Check if all items in chain can be moved
|
|
*/
|
|
for (;;)
|
|
{
|
|
Buffer Pbuf;
|
|
Page Ppage;
|
|
ItemId Pitemid;
|
|
HeapTupleData Ptp;
|
|
VTupleLinkData vtld,
|
|
*vtlp;
|
|
|
|
if (to_vacpage == NULL ||
|
|
!enough_space(to_vacpage, tlen))
|
|
{
|
|
for (i = 0; i < num_fraged_pages; i++)
|
|
{
|
|
if (enough_space(fraged_pages->pagedesc[i], tlen))
|
|
break;
|
|
}
|
|
|
|
if (i == num_fraged_pages)
|
|
{
|
|
/* can't move item anywhere */
|
|
chain_move_failed = true;
|
|
break; /* out of check-all-items loop */
|
|
}
|
|
to_item = i;
|
|
to_vacpage = fraged_pages->pagedesc[to_item];
|
|
}
|
|
to_vacpage->free -= MAXALIGN(tlen);
|
|
if (to_vacpage->offsets_used >= to_vacpage->offsets_free)
|
|
to_vacpage->free -= sizeof(ItemIdData);
|
|
(to_vacpage->offsets_used)++;
|
|
if (free_vtmove == 0)
|
|
{
|
|
free_vtmove = 1000;
|
|
vtmove = (VTupleMove)
|
|
repalloc(vtmove,
|
|
(free_vtmove + num_vtmove) *
|
|
sizeof(VTupleMoveData));
|
|
}
|
|
vtmove[num_vtmove].tid = tp.t_self;
|
|
vtmove[num_vtmove].vacpage = to_vacpage;
|
|
if (to_vacpage->offsets_used == 1)
|
|
vtmove[num_vtmove].cleanVpd = true;
|
|
else
|
|
vtmove[num_vtmove].cleanVpd = false;
|
|
free_vtmove--;
|
|
num_vtmove++;
|
|
|
|
/* At beginning of chain? */
|
|
if (!(tp.t_data->t_infomask & HEAP_UPDATED) ||
|
|
TransactionIdPrecedes(HeapTupleHeaderGetXmin(tp.t_data),
|
|
OldestXmin))
|
|
break;
|
|
|
|
/* No, move to tuple with prior row version */
|
|
vtld.new_tid = tp.t_self;
|
|
vtlp = (VTupleLink)
|
|
vac_bsearch((void *) &vtld,
|
|
(void *) (vacrelstats->vtlinks),
|
|
vacrelstats->num_vtlinks,
|
|
sizeof(VTupleLinkData),
|
|
vac_cmp_vtlinks);
|
|
if (vtlp == NULL)
|
|
{
|
|
/* see discussion above */
|
|
elog(DEBUG2, "parent item in update-chain not found --- can't continue repair_frag");
|
|
chain_move_failed = true;
|
|
break; /* out of check-all-items loop */
|
|
}
|
|
tp.t_self = vtlp->this_tid;
|
|
Pbuf = ReadBuffer(onerel,
|
|
ItemPointerGetBlockNumber(&(tp.t_self)));
|
|
Ppage = BufferGetPage(Pbuf);
|
|
Pitemid = PageGetItemId(Ppage,
|
|
ItemPointerGetOffsetNumber(&(tp.t_self)));
|
|
/* this can't happen since we saw tuple earlier: */
|
|
if (!ItemIdIsUsed(Pitemid))
|
|
elog(ERROR, "parent itemid marked as unused");
|
|
Ptp.t_datamcxt = NULL;
|
|
Ptp.t_data = (HeapTupleHeader) PageGetItem(Ppage, Pitemid);
|
|
|
|
/* ctid should not have changed since we saved it */
|
|
Assert(ItemPointerEquals(&(vtld.new_tid),
|
|
&(Ptp.t_data->t_ctid)));
|
|
|
|
/*
|
|
* Read above about cases when !ItemIdIsUsed(Citemid)
|
|
* (child item is removed)... Due to the fact that at
|
|
* the moment we don't remove unuseful part of
|
|
* update-chain, it's possible to get too old parent
|
|
* row here. Like as in the case which caused this
|
|
* problem, we stop shrinking here. I could try to
|
|
* find real parent row but want not to do it because
|
|
* of real solution will be implemented anyway, later,
|
|
* and we are too close to 6.5 release. - vadim
|
|
* 06/11/99
|
|
*/
|
|
if (Ptp.t_data->t_infomask & HEAP_XMAX_IS_MULTI ||
|
|
!(TransactionIdEquals(HeapTupleHeaderGetXmax(Ptp.t_data),
|
|
HeapTupleHeaderGetXmin(tp.t_data))))
|
|
{
|
|
ReleaseBuffer(Pbuf);
|
|
elog(DEBUG2, "too old parent tuple found --- can't continue repair_frag");
|
|
chain_move_failed = true;
|
|
break; /* out of check-all-items loop */
|
|
}
|
|
tp.t_datamcxt = Ptp.t_datamcxt;
|
|
tp.t_data = Ptp.t_data;
|
|
tlen = tp.t_len = ItemIdGetLength(Pitemid);
|
|
if (freeCbuf)
|
|
ReleaseBuffer(Cbuf);
|
|
Cbuf = Pbuf;
|
|
freeCbuf = true;
|
|
} /* end of check-all-items loop */
|
|
|
|
if (freeCbuf)
|
|
ReleaseBuffer(Cbuf);
|
|
freeCbuf = false;
|
|
|
|
if (chain_move_failed)
|
|
{
|
|
/*
|
|
* Undo changes to offsets_used state. We don't
|
|
* bother cleaning up the amount-free state, since
|
|
* we're not going to do any further tuple motion.
|
|
*/
|
|
for (i = 0; i < num_vtmove; i++)
|
|
{
|
|
Assert(vtmove[i].vacpage->offsets_used > 0);
|
|
(vtmove[i].vacpage->offsets_used)--;
|
|
}
|
|
pfree(vtmove);
|
|
break; /* out of walk-along-page loop */
|
|
}
|
|
|
|
/*
|
|
* Okay, move the whole tuple chain
|
|
*/
|
|
ItemPointerSetInvalid(&Ctid);
|
|
for (ti = 0; ti < num_vtmove; ti++)
|
|
{
|
|
VacPage destvacpage = vtmove[ti].vacpage;
|
|
Page Cpage;
|
|
ItemId Citemid;
|
|
|
|
/* Get page to move from */
|
|
tuple.t_self = vtmove[ti].tid;
|
|
Cbuf = ReadBuffer(onerel,
|
|
ItemPointerGetBlockNumber(&(tuple.t_self)));
|
|
|
|
/* Get page to move to */
|
|
dst_buffer = ReadBuffer(onerel, destvacpage->blkno);
|
|
|
|
LockBuffer(dst_buffer, BUFFER_LOCK_EXCLUSIVE);
|
|
if (dst_buffer != Cbuf)
|
|
LockBuffer(Cbuf, BUFFER_LOCK_EXCLUSIVE);
|
|
|
|
dst_page = BufferGetPage(dst_buffer);
|
|
Cpage = BufferGetPage(Cbuf);
|
|
|
|
Citemid = PageGetItemId(Cpage,
|
|
ItemPointerGetOffsetNumber(&(tuple.t_self)));
|
|
tuple.t_datamcxt = NULL;
|
|
tuple.t_data = (HeapTupleHeader) PageGetItem(Cpage, Citemid);
|
|
tuple_len = tuple.t_len = ItemIdGetLength(Citemid);
|
|
|
|
/*
|
|
* make a copy of the source tuple, and then mark the
|
|
* source tuple MOVED_OFF.
|
|
*/
|
|
move_chain_tuple(onerel, Cbuf, Cpage, &tuple,
|
|
dst_buffer, dst_page, destvacpage,
|
|
&ec, &Ctid, vtmove[ti].cleanVpd);
|
|
|
|
num_moved++;
|
|
if (destvacpage->blkno > last_move_dest_block)
|
|
last_move_dest_block = destvacpage->blkno;
|
|
|
|
/*
|
|
* Remember that we moved tuple from the current page
|
|
* (corresponding index tuple will be cleaned).
|
|
*/
|
|
if (Cbuf == buf)
|
|
vacpage->offsets[vacpage->offsets_free++] =
|
|
ItemPointerGetOffsetNumber(&(tuple.t_self));
|
|
else
|
|
keep_tuples++;
|
|
|
|
WriteBuffer(dst_buffer);
|
|
WriteBuffer(Cbuf);
|
|
} /* end of move-the-tuple-chain loop */
|
|
|
|
dst_buffer = InvalidBuffer;
|
|
pfree(vtmove);
|
|
chain_tuple_moved = true;
|
|
|
|
/* advance to next tuple in walk-along-page loop */
|
|
continue;
|
|
} /* end of is-tuple-in-chain test */
|
|
|
|
/* try to find new page for this tuple */
|
|
if (dst_buffer == InvalidBuffer ||
|
|
!enough_space(dst_vacpage, tuple_len))
|
|
{
|
|
if (dst_buffer != InvalidBuffer)
|
|
{
|
|
WriteBuffer(dst_buffer);
|
|
dst_buffer = InvalidBuffer;
|
|
}
|
|
for (i = 0; i < num_fraged_pages; i++)
|
|
{
|
|
if (enough_space(fraged_pages->pagedesc[i], tuple_len))
|
|
break;
|
|
}
|
|
if (i == num_fraged_pages)
|
|
break; /* can't move item anywhere */
|
|
dst_vacpage = fraged_pages->pagedesc[i];
|
|
dst_buffer = ReadBuffer(onerel, dst_vacpage->blkno);
|
|
LockBuffer(dst_buffer, BUFFER_LOCK_EXCLUSIVE);
|
|
dst_page = BufferGetPage(dst_buffer);
|
|
/* if this page was not used before - clean it */
|
|
if (!PageIsEmpty(dst_page) && dst_vacpage->offsets_used == 0)
|
|
vacuum_page(onerel, dst_buffer, dst_vacpage);
|
|
}
|
|
else
|
|
LockBuffer(dst_buffer, BUFFER_LOCK_EXCLUSIVE);
|
|
|
|
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
|
|
|
|
move_plain_tuple(onerel, buf, page, &tuple,
|
|
dst_buffer, dst_page, dst_vacpage, &ec);
|
|
|
|
|
|
num_moved++;
|
|
if (dst_vacpage->blkno > last_move_dest_block)
|
|
last_move_dest_block = dst_vacpage->blkno;
|
|
|
|
/*
|
|
* Remember that we moved tuple from the current page
|
|
* (corresponding index tuple will be cleaned).
|
|
*/
|
|
vacpage->offsets[vacpage->offsets_free++] = offnum;
|
|
} /* walk along page */
|
|
|
|
/*
|
|
* If we broke out of the walk-along-page loop early (ie, still
|
|
* have offnum <= maxoff), then we failed to move some tuple off
|
|
* this page. No point in shrinking any more, so clean up and
|
|
* exit the per-page loop.
|
|
*/
|
|
if (offnum < maxoff && keep_tuples > 0)
|
|
{
|
|
OffsetNumber off;
|
|
|
|
/*
|
|
* Fix vacpage state for any unvisited tuples remaining on
|
|
* page
|
|
*/
|
|
for (off = OffsetNumberNext(offnum);
|
|
off <= maxoff;
|
|
off = OffsetNumberNext(off))
|
|
{
|
|
ItemId itemid = PageGetItemId(page, off);
|
|
HeapTupleHeader htup;
|
|
|
|
if (!ItemIdIsUsed(itemid))
|
|
continue;
|
|
htup = (HeapTupleHeader) PageGetItem(page, itemid);
|
|
if (htup->t_infomask & HEAP_XMIN_COMMITTED)
|
|
continue;
|
|
|
|
/*
|
|
* See comments in the walk-along-page loop above about
|
|
* why only MOVED_OFF tuples should be found here.
|
|
*/
|
|
if (htup->t_infomask & HEAP_MOVED_IN)
|
|
elog(ERROR, "HEAP_MOVED_IN was not expected");
|
|
if (!(htup->t_infomask & HEAP_MOVED_OFF))
|
|
elog(ERROR, "HEAP_MOVED_OFF was expected");
|
|
if (HeapTupleHeaderGetXvac(htup) != myXID)
|
|
elog(ERROR, "invalid XVAC in tuple header");
|
|
|
|
if (chain_tuple_moved)
|
|
{
|
|
/* some chains were moved while cleaning this page */
|
|
Assert(vacpage->offsets_free > 0);
|
|
for (i = 0; i < vacpage->offsets_free; i++)
|
|
{
|
|
if (vacpage->offsets[i] == off)
|
|
break;
|
|
}
|
|
if (i >= vacpage->offsets_free) /* not found */
|
|
{
|
|
vacpage->offsets[vacpage->offsets_free++] = off;
|
|
Assert(keep_tuples > 0);
|
|
keep_tuples--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
vacpage->offsets[vacpage->offsets_free++] = off;
|
|
Assert(keep_tuples > 0);
|
|
keep_tuples--;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (vacpage->offsets_free > 0) /* some tuples were moved */
|
|
{
|
|
if (chain_tuple_moved) /* else - they are ordered */
|
|
{
|
|
qsort((char *) (vacpage->offsets), vacpage->offsets_free,
|
|
sizeof(OffsetNumber), vac_cmp_offno);
|
|
}
|
|
vpage_insert(&Nvacpagelist, copy_vac_page(vacpage));
|
|
WriteBuffer(buf);
|
|
}
|
|
else if (dowrite)
|
|
WriteBuffer(buf);
|
|
else
|
|
ReleaseBuffer(buf);
|
|
|
|
if (offnum <= maxoff)
|
|
break; /* had to quit early, see above note */
|
|
|
|
} /* walk along relation */
|
|
|
|
blkno++; /* new number of blocks */
|
|
|
|
if (dst_buffer != InvalidBuffer)
|
|
{
|
|
Assert(num_moved > 0);
|
|
WriteBuffer(dst_buffer);
|
|
}
|
|
|
|
if (num_moved > 0)
|
|
{
|
|
/*
|
|
* We have to commit our tuple movings before we truncate the
|
|
* relation. Ideally we should do Commit/StartTransactionCommand
|
|
* here, relying on the session-level table lock to protect our
|
|
* exclusive access to the relation. However, that would require
|
|
* a lot of extra code to close and re-open the relation, indexes,
|
|
* etc. For now, a quick hack: record status of current
|
|
* transaction as committed, and continue.
|
|
*/
|
|
RecordTransactionCommit();
|
|
}
|
|
|
|
/*
|
|
* We are not going to move any more tuples across pages, but we still
|
|
* need to apply vacuum_page to compact free space in the remaining
|
|
* pages in vacuum_pages list. Note that some of these pages may also
|
|
* be in the fraged_pages list, and may have had tuples moved onto
|
|
* them; if so, we already did vacuum_page and needn't do it again.
|
|
*/
|
|
for (i = 0, curpage = vacuum_pages->pagedesc;
|
|
i < vacuumed_pages;
|
|
i++, curpage++)
|
|
{
|
|
vacuum_delay_point();
|
|
|
|
Assert((*curpage)->blkno < blkno);
|
|
if ((*curpage)->offsets_used == 0)
|
|
{
|
|
Buffer buf;
|
|
Page page;
|
|
|
|
/* this page was not used as a move target, so must clean it */
|
|
buf = ReadBuffer(onerel, (*curpage)->blkno);
|
|
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
|
|
page = BufferGetPage(buf);
|
|
if (!PageIsEmpty(page))
|
|
vacuum_page(onerel, buf, *curpage);
|
|
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
|
|
WriteBuffer(buf);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Now scan all the pages that we moved tuples onto and update tuple
|
|
* status bits. This is not really necessary, but will save time for
|
|
* future transactions examining these tuples.
|
|
*/
|
|
update_hint_bits(onerel, fraged_pages, num_fraged_pages,
|
|
last_move_dest_block, num_moved);
|
|
|
|
/*
|
|
* It'd be cleaner to make this report at the bottom of this routine,
|
|
* but then the rusage would double-count the second pass of index
|
|
* vacuuming. So do it here and ignore the relatively small amount of
|
|
* processing that occurs below.
|
|
*/
|
|
ereport(elevel,
|
|
(errmsg("\"%s\": moved %u row versions, truncated %u to %u pages",
|
|
RelationGetRelationName(onerel),
|
|
num_moved, nblocks, blkno),
|
|
errdetail("%s",
|
|
vac_show_rusage(&ru0))));
|
|
|
|
/*
|
|
* Reflect the motion of system tuples to catalog cache here.
|
|
*/
|
|
CommandCounterIncrement();
|
|
|
|
if (Nvacpagelist.num_pages > 0)
|
|
{
|
|
/* vacuum indexes again if needed */
|
|
if (Irel != NULL)
|
|
{
|
|
VacPage *vpleft,
|
|
*vpright,
|
|
vpsave;
|
|
|
|
/* re-sort Nvacpagelist.pagedesc */
|
|
for (vpleft = Nvacpagelist.pagedesc,
|
|
vpright = Nvacpagelist.pagedesc + Nvacpagelist.num_pages - 1;
|
|
vpleft < vpright; vpleft++, vpright--)
|
|
{
|
|
vpsave = *vpleft;
|
|
*vpleft = *vpright;
|
|
*vpright = vpsave;
|
|
}
|
|
|
|
/*
|
|
* keep_tuples is the number of tuples that have been moved
|
|
* off a page during chain moves but not been scanned over
|
|
* subsequently. The tuple ids of these tuples are not
|
|
* recorded as free offsets for any VacPage, so they will not
|
|
* be cleared from the indexes.
|
|
*/
|
|
Assert(keep_tuples >= 0);
|
|
for (i = 0; i < nindexes; i++)
|
|
vacuum_index(&Nvacpagelist, Irel[i],
|
|
vacrelstats->rel_tuples, keep_tuples);
|
|
}
|
|
|
|
/*
|
|
* Clean moved-off tuples from last page in Nvacpagelist list.
|
|
*
|
|
* We need only do this in this one page, because higher-numbered
|
|
* pages are going to be truncated from the relation entirely.
|
|
* But see comments for update_hint_bits().
|
|
*/
|
|
if (vacpage->blkno == (blkno - 1) &&
|
|
vacpage->offsets_free > 0)
|
|
{
|
|
Buffer buf;
|
|
Page page;
|
|
OffsetNumber unused[BLCKSZ / sizeof(OffsetNumber)];
|
|
OffsetNumber offnum,
|
|
maxoff;
|
|
int uncnt;
|
|
int num_tuples = 0;
|
|
|
|
buf = ReadBuffer(onerel, vacpage->blkno);
|
|
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
|
|
page = BufferGetPage(buf);
|
|
maxoff = PageGetMaxOffsetNumber(page);
|
|
for (offnum = FirstOffsetNumber;
|
|
offnum <= maxoff;
|
|
offnum = OffsetNumberNext(offnum))
|
|
{
|
|
ItemId itemid = PageGetItemId(page, offnum);
|
|
HeapTupleHeader htup;
|
|
|
|
if (!ItemIdIsUsed(itemid))
|
|
continue;
|
|
htup = (HeapTupleHeader) PageGetItem(page, itemid);
|
|
if (htup->t_infomask & HEAP_XMIN_COMMITTED)
|
|
continue;
|
|
|
|
/*
|
|
* See comments in the walk-along-page loop above about
|
|
* why only MOVED_OFF tuples should be found here.
|
|
*/
|
|
if (htup->t_infomask & HEAP_MOVED_IN)
|
|
elog(ERROR, "HEAP_MOVED_IN was not expected");
|
|
if (!(htup->t_infomask & HEAP_MOVED_OFF))
|
|
elog(ERROR, "HEAP_MOVED_OFF was expected");
|
|
if (HeapTupleHeaderGetXvac(htup) != myXID)
|
|
elog(ERROR, "invalid XVAC in tuple header");
|
|
|
|
itemid->lp_flags &= ~LP_USED;
|
|
num_tuples++;
|
|
}
|
|
Assert(vacpage->offsets_free == num_tuples);
|
|
|
|
START_CRIT_SECTION();
|
|
|
|
uncnt = PageRepairFragmentation(page, unused);
|
|
|
|
/* XLOG stuff */
|
|
if (!onerel->rd_istemp)
|
|
{
|
|
XLogRecPtr recptr;
|
|
|
|
recptr = log_heap_clean(onerel, buf, unused, uncnt);
|
|
PageSetLSN(page, recptr);
|
|
PageSetTLI(page, ThisTimeLineID);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* No XLOG record, but still need to flag that XID exists
|
|
* on disk
|
|
*/
|
|
MyXactMadeTempRelUpdate = true;
|
|
}
|
|
|
|
END_CRIT_SECTION();
|
|
|
|
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
|
|
WriteBuffer(buf);
|
|
}
|
|
|
|
/* now - free new list of reaped pages */
|
|
curpage = Nvacpagelist.pagedesc;
|
|
for (i = 0; i < Nvacpagelist.num_pages; i++, curpage++)
|
|
pfree(*curpage);
|
|
pfree(Nvacpagelist.pagedesc);
|
|
}
|
|
|
|
/* Truncate relation, if needed */
|
|
if (blkno < nblocks)
|
|
{
|
|
RelationTruncate(onerel, blkno);
|
|
vacrelstats->rel_pages = blkno; /* set new number of blocks */
|
|
}
|
|
|
|
/* clean up */
|
|
pfree(vacpage);
|
|
if (vacrelstats->vtlinks != NULL)
|
|
pfree(vacrelstats->vtlinks);
|
|
|
|
ExecContext_Finish(&ec);
|
|
}
|
|
|
|
/*
|
|
* move_chain_tuple() -- move one tuple that is part of a tuple chain
|
|
*
|
|
* This routine moves old_tup from old_page to dst_page.
|
|
* old_page and dst_page might be the same page.
|
|
* On entry old_buf and dst_buf are locked exclusively, both locks (or
|
|
* the single lock, if this is a intra-page-move) are released before
|
|
* exit.
|
|
*
|
|
* Yes, a routine with ten parameters is ugly, but it's still better
|
|
* than having these 120 lines of code in repair_frag() which is
|
|
* already too long and almost unreadable.
|
|
*/
|
|
static void
|
|
move_chain_tuple(Relation rel,
|
|
Buffer old_buf, Page old_page, HeapTuple old_tup,
|
|
Buffer dst_buf, Page dst_page, VacPage dst_vacpage,
|
|
ExecContext ec, ItemPointer ctid, bool cleanVpd)
|
|
{
|
|
TransactionId myXID = GetCurrentTransactionId();
|
|
HeapTupleData newtup;
|
|
OffsetNumber newoff;
|
|
ItemId newitemid;
|
|
Size tuple_len = old_tup->t_len;
|
|
|
|
heap_copytuple_with_tuple(old_tup, &newtup);
|
|
|
|
/*
|
|
* register invalidation of source tuple in catcaches.
|
|
*/
|
|
CacheInvalidateHeapTuple(rel, old_tup);
|
|
|
|
/* NO EREPORT(ERROR) TILL CHANGES ARE LOGGED */
|
|
START_CRIT_SECTION();
|
|
|
|
old_tup->t_data->t_infomask &= ~(HEAP_XMIN_COMMITTED |
|
|
HEAP_XMIN_INVALID |
|
|
HEAP_MOVED_IN);
|
|
old_tup->t_data->t_infomask |= HEAP_MOVED_OFF;
|
|
HeapTupleHeaderSetXvac(old_tup->t_data, myXID);
|
|
|
|
/*
|
|
* If this page was not used before - clean it.
|
|
*
|
|
* NOTE: a nasty bug used to lurk here. It is possible for the source
|
|
* and destination pages to be the same (since this tuple-chain member
|
|
* can be on a page lower than the one we're currently processing in
|
|
* the outer loop). If that's true, then after vacuum_page() the
|
|
* source tuple will have been moved, and tuple.t_data will be
|
|
* pointing at garbage. Therefore we must do everything that uses
|
|
* old_tup->t_data BEFORE this step!!
|
|
*
|
|
* This path is different from the other callers of vacuum_page, because
|
|
* we have already incremented the vacpage's offsets_used field to
|
|
* account for the tuple(s) we expect to move onto the page. Therefore
|
|
* vacuum_page's check for offsets_used == 0 is wrong. But since
|
|
* that's a good debugging check for all other callers, we work around
|
|
* it here rather than remove it.
|
|
*/
|
|
if (!PageIsEmpty(dst_page) && cleanVpd)
|
|
{
|
|
int sv_offsets_used = dst_vacpage->offsets_used;
|
|
|
|
dst_vacpage->offsets_used = 0;
|
|
vacuum_page(rel, dst_buf, dst_vacpage);
|
|
dst_vacpage->offsets_used = sv_offsets_used;
|
|
}
|
|
|
|
/*
|
|
* Update the state of the copied tuple, and store it on the
|
|
* destination page.
|
|
*/
|
|
newtup.t_data->t_infomask &= ~(HEAP_XMIN_COMMITTED |
|
|
HEAP_XMIN_INVALID |
|
|
HEAP_MOVED_OFF);
|
|
newtup.t_data->t_infomask |= HEAP_MOVED_IN;
|
|
HeapTupleHeaderSetXvac(newtup.t_data, myXID);
|
|
newoff = PageAddItem(dst_page, (Item) newtup.t_data, tuple_len,
|
|
InvalidOffsetNumber, LP_USED);
|
|
if (newoff == InvalidOffsetNumber)
|
|
{
|
|
elog(PANIC, "failed to add item with len = %lu to page %u while moving tuple chain",
|
|
(unsigned long) tuple_len, dst_vacpage->blkno);
|
|
}
|
|
newitemid = PageGetItemId(dst_page, newoff);
|
|
pfree(newtup.t_data);
|
|
newtup.t_datamcxt = NULL;
|
|
newtup.t_data = (HeapTupleHeader) PageGetItem(dst_page, newitemid);
|
|
ItemPointerSet(&(newtup.t_self), dst_vacpage->blkno, newoff);
|
|
|
|
/* XLOG stuff */
|
|
if (!rel->rd_istemp)
|
|
{
|
|
XLogRecPtr recptr = log_heap_move(rel, old_buf, old_tup->t_self,
|
|
dst_buf, &newtup);
|
|
|
|
if (old_buf != dst_buf)
|
|
{
|
|
PageSetLSN(old_page, recptr);
|
|
PageSetTLI(old_page, ThisTimeLineID);
|
|
}
|
|
PageSetLSN(dst_page, recptr);
|
|
PageSetTLI(dst_page, ThisTimeLineID);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* No XLOG record, but still need to flag that XID exists on disk
|
|
*/
|
|
MyXactMadeTempRelUpdate = true;
|
|
}
|
|
|
|
END_CRIT_SECTION();
|
|
|
|
/*
|
|
* Set new tuple's t_ctid pointing to itself for last tuple in chain,
|
|
* and to next tuple in chain otherwise.
|
|
*/
|
|
/* Is this ok after log_heap_move() and END_CRIT_SECTION()? */
|
|
if (!ItemPointerIsValid(ctid))
|
|
newtup.t_data->t_ctid = newtup.t_self;
|
|
else
|
|
newtup.t_data->t_ctid = *ctid;
|
|
*ctid = newtup.t_self;
|
|
|
|
LockBuffer(dst_buf, BUFFER_LOCK_UNLOCK);
|
|
if (dst_buf != old_buf)
|
|
LockBuffer(old_buf, BUFFER_LOCK_UNLOCK);
|
|
|
|
/* Create index entries for the moved tuple */
|
|
if (ec->resultRelInfo->ri_NumIndices > 0)
|
|
{
|
|
ExecStoreTuple(&newtup, ec->slot, InvalidBuffer, false);
|
|
ExecInsertIndexTuples(ec->slot, &(newtup.t_self), ec->estate, true);
|
|
ResetPerTupleExprContext(ec->estate);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* move_plain_tuple() -- move one tuple that is not part of a chain
|
|
*
|
|
* This routine moves old_tup from old_page to dst_page.
|
|
* On entry old_buf and dst_buf are locked exclusively, both locks are
|
|
* released before exit.
|
|
*
|
|
* Yes, a routine with eight parameters is ugly, but it's still better
|
|
* than having these 90 lines of code in repair_frag() which is already
|
|
* too long and almost unreadable.
|
|
*/
|
|
static void
|
|
move_plain_tuple(Relation rel,
|
|
Buffer old_buf, Page old_page, HeapTuple old_tup,
|
|
Buffer dst_buf, Page dst_page, VacPage dst_vacpage,
|
|
ExecContext ec)
|
|
{
|
|
TransactionId myXID = GetCurrentTransactionId();
|
|
HeapTupleData newtup;
|
|
OffsetNumber newoff;
|
|
ItemId newitemid;
|
|
Size tuple_len = old_tup->t_len;
|
|
|
|
/* copy tuple */
|
|
heap_copytuple_with_tuple(old_tup, &newtup);
|
|
|
|
/*
|
|
* register invalidation of source tuple in catcaches.
|
|
*
|
|
* (Note: we do not need to register the copied tuple, because we are not
|
|
* changing the tuple contents and so there cannot be any need to
|
|
* flush negative catcache entries.)
|
|
*/
|
|
CacheInvalidateHeapTuple(rel, old_tup);
|
|
|
|
/* NO EREPORT(ERROR) TILL CHANGES ARE LOGGED */
|
|
START_CRIT_SECTION();
|
|
|
|
/*
|
|
* Mark new tuple as MOVED_IN by me.
|
|
*/
|
|
newtup.t_data->t_infomask &= ~(HEAP_XMIN_COMMITTED |
|
|
HEAP_XMIN_INVALID |
|
|
HEAP_MOVED_OFF);
|
|
newtup.t_data->t_infomask |= HEAP_MOVED_IN;
|
|
HeapTupleHeaderSetXvac(newtup.t_data, myXID);
|
|
|
|
/* add tuple to the page */
|
|
newoff = PageAddItem(dst_page, (Item) newtup.t_data, tuple_len,
|
|
InvalidOffsetNumber, LP_USED);
|
|
if (newoff == InvalidOffsetNumber)
|
|
{
|
|
elog(PANIC, "failed to add item with len = %lu to page %u (free space %lu, nusd %u, noff %u)",
|
|
(unsigned long) tuple_len,
|
|
dst_vacpage->blkno, (unsigned long) dst_vacpage->free,
|
|
dst_vacpage->offsets_used, dst_vacpage->offsets_free);
|
|
}
|
|
newitemid = PageGetItemId(dst_page, newoff);
|
|
pfree(newtup.t_data);
|
|
newtup.t_datamcxt = NULL;
|
|
newtup.t_data = (HeapTupleHeader) PageGetItem(dst_page, newitemid);
|
|
ItemPointerSet(&(newtup.t_data->t_ctid), dst_vacpage->blkno, newoff);
|
|
newtup.t_self = newtup.t_data->t_ctid;
|
|
|
|
/*
|
|
* Mark old tuple as MOVED_OFF by me.
|
|
*/
|
|
old_tup->t_data->t_infomask &= ~(HEAP_XMIN_COMMITTED |
|
|
HEAP_XMIN_INVALID |
|
|
HEAP_MOVED_IN);
|
|
old_tup->t_data->t_infomask |= HEAP_MOVED_OFF;
|
|
HeapTupleHeaderSetXvac(old_tup->t_data, myXID);
|
|
|
|
/* XLOG stuff */
|
|
if (!rel->rd_istemp)
|
|
{
|
|
XLogRecPtr recptr = log_heap_move(rel, old_buf, old_tup->t_self,
|
|
dst_buf, &newtup);
|
|
|
|
PageSetLSN(old_page, recptr);
|
|
PageSetTLI(old_page, ThisTimeLineID);
|
|
PageSetLSN(dst_page, recptr);
|
|
PageSetTLI(dst_page, ThisTimeLineID);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* No XLOG record, but still need to flag that XID exists on disk
|
|
*/
|
|
MyXactMadeTempRelUpdate = true;
|
|
}
|
|
|
|
END_CRIT_SECTION();
|
|
|
|
dst_vacpage->free = ((PageHeader) dst_page)->pd_upper -
|
|
((PageHeader) dst_page)->pd_lower;
|
|
LockBuffer(dst_buf, BUFFER_LOCK_UNLOCK);
|
|
LockBuffer(old_buf, BUFFER_LOCK_UNLOCK);
|
|
|
|
dst_vacpage->offsets_used++;
|
|
|
|
/* insert index' tuples if needed */
|
|
if (ec->resultRelInfo->ri_NumIndices > 0)
|
|
{
|
|
ExecStoreTuple(&newtup, ec->slot, InvalidBuffer, false);
|
|
ExecInsertIndexTuples(ec->slot, &(newtup.t_self), ec->estate, true);
|
|
ResetPerTupleExprContext(ec->estate);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* update_hint_bits() -- update hint bits in destination pages
|
|
*
|
|
* Scan all the pages that we moved tuples onto and update tuple status bits.
|
|
* This is normally not really necessary, but it will save time for future
|
|
* transactions examining these tuples.
|
|
*
|
|
* This pass guarantees that all HEAP_MOVED_IN tuples are marked as
|
|
* XMIN_COMMITTED, so that future tqual tests won't need to check their XVAC.
|
|
*
|
|
* BUT NOTICE that this code fails to clear HEAP_MOVED_OFF tuples from
|
|
* pages that were move source pages but not move dest pages. The bulk
|
|
* of the move source pages will be physically truncated from the relation,
|
|
* and the last page remaining in the rel will be fixed separately in
|
|
* repair_frag(), so the only cases where a MOVED_OFF tuple won't get its
|
|
* hint bits updated are tuples that are moved as part of a chain and were
|
|
* on pages that were not either move destinations nor at the end of the rel.
|
|
* To completely ensure that no MOVED_OFF tuples remain unmarked, we'd have
|
|
* to remember and revisit those pages too.
|
|
*
|
|
* Because of this omission, VACUUM FULL FREEZE is not a safe combination;
|
|
* it's possible that the VACUUM's own XID remains exposed as something that
|
|
* tqual tests would need to check.
|
|
*
|
|
* For the non-freeze case, one wonders whether it wouldn't be better to skip
|
|
* this work entirely, and let the tuple status updates happen someplace
|
|
* that's not holding an exclusive lock on the relation.
|
|
*/
|
|
static void
|
|
update_hint_bits(Relation rel, VacPageList fraged_pages, int num_fraged_pages,
|
|
BlockNumber last_move_dest_block, int num_moved)
|
|
{
|
|
TransactionId myXID = GetCurrentTransactionId();
|
|
int checked_moved = 0;
|
|
int i;
|
|
VacPage *curpage;
|
|
|
|
for (i = 0, curpage = fraged_pages->pagedesc;
|
|
i < num_fraged_pages;
|
|
i++, curpage++)
|
|
{
|
|
Buffer buf;
|
|
Page page;
|
|
OffsetNumber max_offset;
|
|
OffsetNumber off;
|
|
int num_tuples = 0;
|
|
|
|
vacuum_delay_point();
|
|
|
|
if ((*curpage)->blkno > last_move_dest_block)
|
|
break; /* no need to scan any further */
|
|
if ((*curpage)->offsets_used == 0)
|
|
continue; /* this page was never used as a move dest */
|
|
buf = ReadBuffer(rel, (*curpage)->blkno);
|
|
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
|
|
page = BufferGetPage(buf);
|
|
max_offset = PageGetMaxOffsetNumber(page);
|
|
for (off = FirstOffsetNumber;
|
|
off <= max_offset;
|
|
off = OffsetNumberNext(off))
|
|
{
|
|
ItemId itemid = PageGetItemId(page, off);
|
|
HeapTupleHeader htup;
|
|
|
|
if (!ItemIdIsUsed(itemid))
|
|
continue;
|
|
htup = (HeapTupleHeader) PageGetItem(page, itemid);
|
|
if (htup->t_infomask & HEAP_XMIN_COMMITTED)
|
|
continue;
|
|
|
|
/*
|
|
* Here we may see either MOVED_OFF or MOVED_IN tuples.
|
|
*/
|
|
if (!(htup->t_infomask & HEAP_MOVED))
|
|
elog(ERROR, "HEAP_MOVED_OFF/HEAP_MOVED_IN was expected");
|
|
if (HeapTupleHeaderGetXvac(htup) != myXID)
|
|
elog(ERROR, "invalid XVAC in tuple header");
|
|
|
|
if (htup->t_infomask & HEAP_MOVED_IN)
|
|
{
|
|
htup->t_infomask |= HEAP_XMIN_COMMITTED;
|
|
htup->t_infomask &= ~HEAP_MOVED;
|
|
num_tuples++;
|
|
}
|
|
else
|
|
htup->t_infomask |= HEAP_XMIN_INVALID;
|
|
}
|
|
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
|
|
WriteBuffer(buf);
|
|
Assert((*curpage)->offsets_used == num_tuples);
|
|
checked_moved += num_tuples;
|
|
}
|
|
Assert(num_moved == checked_moved);
|
|
}
|
|
|
|
/*
|
|
* vacuum_heap() -- free dead tuples
|
|
*
|
|
* This routine marks dead tuples as unused and truncates relation
|
|
* if there are "empty" end-blocks.
|
|
*/
|
|
static void
|
|
vacuum_heap(VRelStats *vacrelstats, Relation onerel, VacPageList vacuum_pages)
|
|
{
|
|
Buffer buf;
|
|
VacPage *vacpage;
|
|
BlockNumber relblocks;
|
|
int nblocks;
|
|
int i;
|
|
|
|
nblocks = vacuum_pages->num_pages;
|
|
nblocks -= vacuum_pages->empty_end_pages; /* nothing to do with them */
|
|
|
|
for (i = 0, vacpage = vacuum_pages->pagedesc; i < nblocks; i++, vacpage++)
|
|
{
|
|
vacuum_delay_point();
|
|
|
|
if ((*vacpage)->offsets_free > 0)
|
|
{
|
|
buf = ReadBuffer(onerel, (*vacpage)->blkno);
|
|
LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
|
|
vacuum_page(onerel, buf, *vacpage);
|
|
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
|
|
WriteBuffer(buf);
|
|
}
|
|
}
|
|
|
|
/* Truncate relation if there are some empty end-pages */
|
|
Assert(vacrelstats->rel_pages >= vacuum_pages->empty_end_pages);
|
|
if (vacuum_pages->empty_end_pages > 0)
|
|
{
|
|
relblocks = vacrelstats->rel_pages - vacuum_pages->empty_end_pages;
|
|
ereport(elevel,
|
|
(errmsg("\"%s\": truncated %u to %u pages",
|
|
RelationGetRelationName(onerel),
|
|
vacrelstats->rel_pages, relblocks)));
|
|
RelationTruncate(onerel, relblocks);
|
|
vacrelstats->rel_pages = relblocks; /* set new number of blocks */
|
|
}
|
|
}
|
|
|
|
/*
|
|
* vacuum_page() -- free dead tuples on a page
|
|
* and repair its fragmentation.
|
|
*/
|
|
static void
|
|
vacuum_page(Relation onerel, Buffer buffer, VacPage vacpage)
|
|
{
|
|
OffsetNumber unused[BLCKSZ / sizeof(OffsetNumber)];
|
|
int uncnt;
|
|
Page page = BufferGetPage(buffer);
|
|
ItemId itemid;
|
|
int i;
|
|
|
|
/* There shouldn't be any tuples moved onto the page yet! */
|
|
Assert(vacpage->offsets_used == 0);
|
|
|
|
START_CRIT_SECTION();
|
|
|
|
for (i = 0; i < vacpage->offsets_free; i++)
|
|
{
|
|
itemid = PageGetItemId(page, vacpage->offsets[i]);
|
|
itemid->lp_flags &= ~LP_USED;
|
|
}
|
|
|
|
uncnt = PageRepairFragmentation(page, unused);
|
|
|
|
/* XLOG stuff */
|
|
if (!onerel->rd_istemp)
|
|
{
|
|
XLogRecPtr recptr;
|
|
|
|
recptr = log_heap_clean(onerel, buffer, unused, uncnt);
|
|
PageSetLSN(page, recptr);
|
|
PageSetTLI(page, ThisTimeLineID);
|
|
}
|
|
else
|
|
{
|
|
/* No XLOG record, but still need to flag that XID exists on disk */
|
|
MyXactMadeTempRelUpdate = true;
|
|
}
|
|
|
|
END_CRIT_SECTION();
|
|
}
|
|
|
|
/*
|
|
* scan_index() -- scan one index relation to update statistic.
|
|
*
|
|
* We use this when we have no deletions to do.
|
|
*/
|
|
static void
|
|
scan_index(Relation indrel, double num_tuples)
|
|
{
|
|
IndexBulkDeleteResult *stats;
|
|
IndexVacuumCleanupInfo vcinfo;
|
|
VacRUsage ru0;
|
|
|
|
vac_init_rusage(&ru0);
|
|
|
|
/*
|
|
* Even though we're not planning to delete anything, we use the
|
|
* ambulkdelete call, because (a) the scan happens within the index AM
|
|
* for more speed, and (b) it may want to pass private statistics to
|
|
* the amvacuumcleanup call.
|
|
*/
|
|
stats = index_bulk_delete(indrel, dummy_tid_reaped, NULL);
|
|
|
|
/* Do post-VACUUM cleanup, even though we deleted nothing */
|
|
vcinfo.vacuum_full = true;
|
|
vcinfo.message_level = elevel;
|
|
|
|
stats = index_vacuum_cleanup(indrel, &vcinfo, stats);
|
|
|
|
if (!stats)
|
|
return;
|
|
|
|
/* now update statistics in pg_class */
|
|
vac_update_relstats(RelationGetRelid(indrel),
|
|
stats->num_pages, stats->num_index_tuples,
|
|
false);
|
|
|
|
ereport(elevel,
|
|
(errmsg("index \"%s\" now contains %.0f row versions in %u pages",
|
|
RelationGetRelationName(indrel),
|
|
stats->num_index_tuples,
|
|
stats->num_pages),
|
|
errdetail("%u index pages have been deleted, %u are currently reusable.\n"
|
|
"%s",
|
|
stats->pages_deleted, stats->pages_free,
|
|
vac_show_rusage(&ru0))));
|
|
|
|
/*
|
|
* Check for tuple count mismatch. If the index is partial, then it's
|
|
* OK for it to have fewer tuples than the heap; else we got trouble.
|
|
*/
|
|
if (stats->num_index_tuples != num_tuples)
|
|
{
|
|
if (stats->num_index_tuples > num_tuples ||
|
|
!vac_is_partial_index(indrel))
|
|
ereport(WARNING,
|
|
(errmsg("index \"%s\" contains %.0f row versions, but table contains %.0f row versions",
|
|
RelationGetRelationName(indrel),
|
|
stats->num_index_tuples, num_tuples),
|
|
errhint("Rebuild the index with REINDEX.")));
|
|
}
|
|
|
|
pfree(stats);
|
|
}
|
|
|
|
/*
|
|
* vacuum_index() -- vacuum one index relation.
|
|
*
|
|
* Vpl is the VacPageList of the heap we're currently vacuuming.
|
|
* It's locked. Indrel is an index relation on the vacuumed heap.
|
|
*
|
|
* We don't bother to set locks on the index relation here, since
|
|
* the parent table is exclusive-locked already.
|
|
*
|
|
* Finally, we arrange to update the index relation's statistics in
|
|
* pg_class.
|
|
*/
|
|
static void
|
|
vacuum_index(VacPageList vacpagelist, Relation indrel,
|
|
double num_tuples, int keep_tuples)
|
|
{
|
|
IndexBulkDeleteResult *stats;
|
|
IndexVacuumCleanupInfo vcinfo;
|
|
VacRUsage ru0;
|
|
|
|
vac_init_rusage(&ru0);
|
|
|
|
/* Do bulk deletion */
|
|
stats = index_bulk_delete(indrel, tid_reaped, (void *) vacpagelist);
|
|
|
|
/* Do post-VACUUM cleanup */
|
|
vcinfo.vacuum_full = true;
|
|
vcinfo.message_level = elevel;
|
|
|
|
stats = index_vacuum_cleanup(indrel, &vcinfo, stats);
|
|
|
|
if (!stats)
|
|
return;
|
|
|
|
/* now update statistics in pg_class */
|
|
vac_update_relstats(RelationGetRelid(indrel),
|
|
stats->num_pages, stats->num_index_tuples,
|
|
false);
|
|
|
|
ereport(elevel,
|
|
(errmsg("index \"%s\" now contains %.0f row versions in %u pages",
|
|
RelationGetRelationName(indrel),
|
|
stats->num_index_tuples,
|
|
stats->num_pages),
|
|
errdetail("%.0f index row versions were removed.\n"
|
|
"%u index pages have been deleted, %u are currently reusable.\n"
|
|
"%s",
|
|
stats->tuples_removed,
|
|
stats->pages_deleted, stats->pages_free,
|
|
vac_show_rusage(&ru0))));
|
|
|
|
/*
|
|
* Check for tuple count mismatch. If the index is partial, then it's
|
|
* OK for it to have fewer tuples than the heap; else we got trouble.
|
|
*/
|
|
if (stats->num_index_tuples != num_tuples + keep_tuples)
|
|
{
|
|
if (stats->num_index_tuples > num_tuples + keep_tuples ||
|
|
!vac_is_partial_index(indrel))
|
|
ereport(WARNING,
|
|
(errmsg("index \"%s\" contains %.0f row versions, but table contains %.0f row versions",
|
|
RelationGetRelationName(indrel),
|
|
stats->num_index_tuples, num_tuples + keep_tuples),
|
|
errhint("Rebuild the index with REINDEX.")));
|
|
}
|
|
|
|
pfree(stats);
|
|
}
|
|
|
|
/*
|
|
* tid_reaped() -- is a particular tid reaped?
|
|
*
|
|
* This has the right signature to be an IndexBulkDeleteCallback.
|
|
*
|
|
* vacpagelist->VacPage_array is sorted in right order.
|
|
*/
|
|
static bool
|
|
tid_reaped(ItemPointer itemptr, void *state)
|
|
{
|
|
VacPageList vacpagelist = (VacPageList) state;
|
|
OffsetNumber ioffno;
|
|
OffsetNumber *voff;
|
|
VacPage vp,
|
|
*vpp;
|
|
VacPageData vacpage;
|
|
|
|
vacpage.blkno = ItemPointerGetBlockNumber(itemptr);
|
|
ioffno = ItemPointerGetOffsetNumber(itemptr);
|
|
|
|
vp = &vacpage;
|
|
vpp = (VacPage *) vac_bsearch((void *) &vp,
|
|
(void *) (vacpagelist->pagedesc),
|
|
vacpagelist->num_pages,
|
|
sizeof(VacPage),
|
|
vac_cmp_blk);
|
|
|
|
if (vpp == NULL)
|
|
return false;
|
|
|
|
/* ok - we are on a partially or fully reaped page */
|
|
vp = *vpp;
|
|
|
|
if (vp->offsets_free == 0)
|
|
{
|
|
/* this is EmptyPage, so claim all tuples on it are reaped!!! */
|
|
return true;
|
|
}
|
|
|
|
voff = (OffsetNumber *) vac_bsearch((void *) &ioffno,
|
|
(void *) (vp->offsets),
|
|
vp->offsets_free,
|
|
sizeof(OffsetNumber),
|
|
vac_cmp_offno);
|
|
|
|
if (voff == NULL)
|
|
return false;
|
|
|
|
/* tid is reaped */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Dummy version for scan_index.
|
|
*/
|
|
static bool
|
|
dummy_tid_reaped(ItemPointer itemptr, void *state)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Update the shared Free Space Map with the info we now have about
|
|
* free space in the relation, discarding any old info the map may have.
|
|
*/
|
|
static void
|
|
vac_update_fsm(Relation onerel, VacPageList fraged_pages,
|
|
BlockNumber rel_pages)
|
|
{
|
|
int nPages = fraged_pages->num_pages;
|
|
VacPage *pagedesc = fraged_pages->pagedesc;
|
|
Size threshold;
|
|
PageFreeSpaceInfo *pageSpaces;
|
|
int outPages;
|
|
int i;
|
|
|
|
/*
|
|
* We only report pages with free space at least equal to the average
|
|
* request size --- this avoids cluttering FSM with uselessly-small
|
|
* bits of space. Although FSM would discard pages with little free
|
|
* space anyway, it's important to do this prefiltering because (a) it
|
|
* reduces the time spent holding the FSM lock in
|
|
* RecordRelationFreeSpace, and (b) FSM uses the number of pages
|
|
* reported as a statistic for guiding space management. If we didn't
|
|
* threshold our reports the same way vacuumlazy.c does, we'd be
|
|
* skewing that statistic.
|
|
*/
|
|
threshold = GetAvgFSMRequestSize(&onerel->rd_node);
|
|
|
|
pageSpaces = (PageFreeSpaceInfo *)
|
|
palloc(nPages * sizeof(PageFreeSpaceInfo));
|
|
outPages = 0;
|
|
|
|
for (i = 0; i < nPages; i++)
|
|
{
|
|
/*
|
|
* fraged_pages may contain entries for pages that we later
|
|
* decided to truncate from the relation; don't enter them into
|
|
* the free space map!
|
|
*/
|
|
if (pagedesc[i]->blkno >= rel_pages)
|
|
break;
|
|
|
|
if (pagedesc[i]->free >= threshold)
|
|
{
|
|
pageSpaces[outPages].blkno = pagedesc[i]->blkno;
|
|
pageSpaces[outPages].avail = pagedesc[i]->free;
|
|
outPages++;
|
|
}
|
|
}
|
|
|
|
RecordRelationFreeSpace(&onerel->rd_node, outPages, pageSpaces);
|
|
|
|
pfree(pageSpaces);
|
|
}
|
|
|
|
/* Copy a VacPage structure */
|
|
static VacPage
|
|
copy_vac_page(VacPage vacpage)
|
|
{
|
|
VacPage newvacpage;
|
|
|
|
/* allocate a VacPageData entry */
|
|
newvacpage = (VacPage) palloc(sizeof(VacPageData) +
|
|
vacpage->offsets_free * sizeof(OffsetNumber));
|
|
|
|
/* fill it in */
|
|
if (vacpage->offsets_free > 0)
|
|
memcpy(newvacpage->offsets, vacpage->offsets,
|
|
vacpage->offsets_free * sizeof(OffsetNumber));
|
|
newvacpage->blkno = vacpage->blkno;
|
|
newvacpage->free = vacpage->free;
|
|
newvacpage->offsets_used = vacpage->offsets_used;
|
|
newvacpage->offsets_free = vacpage->offsets_free;
|
|
|
|
return newvacpage;
|
|
}
|
|
|
|
/*
|
|
* Add a VacPage pointer to a VacPageList.
|
|
*
|
|
* As a side effect of the way that scan_heap works,
|
|
* higher pages come after lower pages in the array
|
|
* (and highest tid on a page is last).
|
|
*/
|
|
static void
|
|
vpage_insert(VacPageList vacpagelist, VacPage vpnew)
|
|
{
|
|
#define PG_NPAGEDESC 1024
|
|
|
|
/* allocate a VacPage entry if needed */
|
|
if (vacpagelist->num_pages == 0)
|
|
{
|
|
vacpagelist->pagedesc = (VacPage *) palloc(PG_NPAGEDESC * sizeof(VacPage));
|
|
vacpagelist->num_allocated_pages = PG_NPAGEDESC;
|
|
}
|
|
else if (vacpagelist->num_pages >= vacpagelist->num_allocated_pages)
|
|
{
|
|
vacpagelist->num_allocated_pages *= 2;
|
|
vacpagelist->pagedesc = (VacPage *) repalloc(vacpagelist->pagedesc, vacpagelist->num_allocated_pages * sizeof(VacPage));
|
|
}
|
|
vacpagelist->pagedesc[vacpagelist->num_pages] = vpnew;
|
|
(vacpagelist->num_pages)++;
|
|
}
|
|
|
|
/*
|
|
* vac_bsearch: just like standard C library routine bsearch(),
|
|
* except that we first test to see whether the target key is outside
|
|
* the range of the table entries. This case is handled relatively slowly
|
|
* by the normal binary search algorithm (ie, no faster than any other key)
|
|
* but it occurs often enough in VACUUM to be worth optimizing.
|
|
*/
|
|
static void *
|
|
vac_bsearch(const void *key, const void *base,
|
|
size_t nelem, size_t size,
|
|
int (*compar) (const void *, const void *))
|
|
{
|
|
int res;
|
|
const void *last;
|
|
|
|
if (nelem == 0)
|
|
return NULL;
|
|
res = compar(key, base);
|
|
if (res < 0)
|
|
return NULL;
|
|
if (res == 0)
|
|
return (void *) base;
|
|
if (nelem > 1)
|
|
{
|
|
last = (const void *) ((const char *) base + (nelem - 1) * size);
|
|
res = compar(key, last);
|
|
if (res > 0)
|
|
return NULL;
|
|
if (res == 0)
|
|
return (void *) last;
|
|
}
|
|
if (nelem <= 2)
|
|
return NULL; /* already checked 'em all */
|
|
return bsearch(key, base, nelem, size, compar);
|
|
}
|
|
|
|
/*
|
|
* Comparator routines for use with qsort() and bsearch().
|
|
*/
|
|
static int
|
|
vac_cmp_blk(const void *left, const void *right)
|
|
{
|
|
BlockNumber lblk,
|
|
rblk;
|
|
|
|
lblk = (*((VacPage *) left))->blkno;
|
|
rblk = (*((VacPage *) right))->blkno;
|
|
|
|
if (lblk < rblk)
|
|
return -1;
|
|
if (lblk == rblk)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
vac_cmp_offno(const void *left, const void *right)
|
|
{
|
|
if (*(OffsetNumber *) left < *(OffsetNumber *) right)
|
|
return -1;
|
|
if (*(OffsetNumber *) left == *(OffsetNumber *) right)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
vac_cmp_vtlinks(const void *left, const void *right)
|
|
{
|
|
if (((VTupleLink) left)->new_tid.ip_blkid.bi_hi <
|
|
((VTupleLink) right)->new_tid.ip_blkid.bi_hi)
|
|
return -1;
|
|
if (((VTupleLink) left)->new_tid.ip_blkid.bi_hi >
|
|
((VTupleLink) right)->new_tid.ip_blkid.bi_hi)
|
|
return 1;
|
|
/* bi_hi-es are equal */
|
|
if (((VTupleLink) left)->new_tid.ip_blkid.bi_lo <
|
|
((VTupleLink) right)->new_tid.ip_blkid.bi_lo)
|
|
return -1;
|
|
if (((VTupleLink) left)->new_tid.ip_blkid.bi_lo >
|
|
((VTupleLink) right)->new_tid.ip_blkid.bi_lo)
|
|
return 1;
|
|
/* bi_lo-es are equal */
|
|
if (((VTupleLink) left)->new_tid.ip_posid <
|
|
((VTupleLink) right)->new_tid.ip_posid)
|
|
return -1;
|
|
if (((VTupleLink) left)->new_tid.ip_posid >
|
|
((VTupleLink) right)->new_tid.ip_posid)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Open all the indexes of the given relation, obtaining the specified kind
|
|
* of lock on each. Return an array of Relation pointers for the indexes
|
|
* into *Irel, and the number of indexes into *nindexes.
|
|
*/
|
|
void
|
|
vac_open_indexes(Relation relation, LOCKMODE lockmode,
|
|
int *nindexes, Relation **Irel)
|
|
{
|
|
List *indexoidlist;
|
|
ListCell *indexoidscan;
|
|
int i;
|
|
|
|
indexoidlist = RelationGetIndexList(relation);
|
|
|
|
*nindexes = list_length(indexoidlist);
|
|
|
|
if (*nindexes > 0)
|
|
*Irel = (Relation *) palloc(*nindexes * sizeof(Relation));
|
|
else
|
|
*Irel = NULL;
|
|
|
|
i = 0;
|
|
foreach(indexoidscan, indexoidlist)
|
|
{
|
|
Oid indexoid = lfirst_oid(indexoidscan);
|
|
Relation ind;
|
|
|
|
ind = index_open(indexoid);
|
|
(*Irel)[i++] = ind;
|
|
LockRelation(ind, lockmode);
|
|
}
|
|
|
|
list_free(indexoidlist);
|
|
}
|
|
|
|
/*
|
|
* Release the resources acquired by vac_open_indexes. Optionally release
|
|
* the locks (say NoLock to keep 'em).
|
|
*/
|
|
void
|
|
vac_close_indexes(int nindexes, Relation *Irel, LOCKMODE lockmode)
|
|
{
|
|
if (Irel == NULL)
|
|
return;
|
|
|
|
while (nindexes--)
|
|
{
|
|
Relation ind = Irel[nindexes];
|
|
|
|
if (lockmode != NoLock)
|
|
UnlockRelation(ind, lockmode);
|
|
index_close(ind);
|
|
}
|
|
pfree(Irel);
|
|
}
|
|
|
|
|
|
/*
|
|
* Is an index partial (ie, could it contain fewer tuples than the heap?)
|
|
*/
|
|
bool
|
|
vac_is_partial_index(Relation indrel)
|
|
{
|
|
/*
|
|
* If the index's AM doesn't support nulls, it's partial for our
|
|
* purposes
|
|
*/
|
|
if (!indrel->rd_am->amindexnulls)
|
|
return true;
|
|
|
|
/* Otherwise, look to see if there's a partial-index predicate */
|
|
if (!heap_attisnull(indrel->rd_indextuple, Anum_pg_index_indpred))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
static bool
|
|
enough_space(VacPage vacpage, Size len)
|
|
{
|
|
len = MAXALIGN(len);
|
|
|
|
if (len > vacpage->free)
|
|
return false;
|
|
|
|
/* if there are free itemid(s) and len <= free_space... */
|
|
if (vacpage->offsets_used < vacpage->offsets_free)
|
|
return true;
|
|
|
|
/* noff_used >= noff_free and so we'll have to allocate new itemid */
|
|
if (len + sizeof(ItemIdData) <= vacpage->free)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
/*
|
|
* Initialize usage snapshot.
|
|
*/
|
|
void
|
|
vac_init_rusage(VacRUsage *ru0)
|
|
{
|
|
struct timezone tz;
|
|
|
|
getrusage(RUSAGE_SELF, &ru0->ru);
|
|
gettimeofday(&ru0->tv, &tz);
|
|
}
|
|
|
|
/*
|
|
* Compute elapsed time since ru0 usage snapshot, and format into
|
|
* a displayable string. Result is in a static string, which is
|
|
* tacky, but no one ever claimed that the Postgres backend is
|
|
* threadable...
|
|
*/
|
|
const char *
|
|
vac_show_rusage(VacRUsage *ru0)
|
|
{
|
|
static char result[100];
|
|
VacRUsage ru1;
|
|
|
|
vac_init_rusage(&ru1);
|
|
|
|
if (ru1.tv.tv_usec < ru0->tv.tv_usec)
|
|
{
|
|
ru1.tv.tv_sec--;
|
|
ru1.tv.tv_usec += 1000000;
|
|
}
|
|
if (ru1.ru.ru_stime.tv_usec < ru0->ru.ru_stime.tv_usec)
|
|
{
|
|
ru1.ru.ru_stime.tv_sec--;
|
|
ru1.ru.ru_stime.tv_usec += 1000000;
|
|
}
|
|
if (ru1.ru.ru_utime.tv_usec < ru0->ru.ru_utime.tv_usec)
|
|
{
|
|
ru1.ru.ru_utime.tv_sec--;
|
|
ru1.ru.ru_utime.tv_usec += 1000000;
|
|
}
|
|
|
|
snprintf(result, sizeof(result),
|
|
"CPU %d.%02ds/%d.%02du sec elapsed %d.%02d sec.",
|
|
(int) (ru1.ru.ru_stime.tv_sec - ru0->ru.ru_stime.tv_sec),
|
|
(int) (ru1.ru.ru_stime.tv_usec - ru0->ru.ru_stime.tv_usec) / 10000,
|
|
(int) (ru1.ru.ru_utime.tv_sec - ru0->ru.ru_utime.tv_sec),
|
|
(int) (ru1.ru.ru_utime.tv_usec - ru0->ru.ru_utime.tv_usec) / 10000,
|
|
(int) (ru1.tv.tv_sec - ru0->tv.tv_sec),
|
|
(int) (ru1.tv.tv_usec - ru0->tv.tv_usec) / 10000);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* vacuum_delay_point --- check for interrupts and cost-based delay.
|
|
*
|
|
* This should be called in each major loop of VACUUM processing,
|
|
* typically once per page processed.
|
|
*/
|
|
void
|
|
vacuum_delay_point(void)
|
|
{
|
|
/* Always check for interrupts */
|
|
CHECK_FOR_INTERRUPTS();
|
|
|
|
/* Nap if appropriate */
|
|
if (VacuumCostActive && !InterruptPending &&
|
|
VacuumCostBalance >= VacuumCostLimit)
|
|
{
|
|
int msec;
|
|
|
|
msec = VacuumCostDelay * VacuumCostBalance / VacuumCostLimit;
|
|
if (msec > VacuumCostDelay * 4)
|
|
msec = VacuumCostDelay * 4;
|
|
|
|
pg_usleep(msec * 1000L);
|
|
|
|
VacuumCostBalance = 0;
|
|
|
|
/* Might have gotten an interrupt while sleeping */
|
|
CHECK_FOR_INTERRUPTS();
|
|
}
|
|
}
|