Implement backup API functions for non-exclusive backups

Previously non-exclusive backups had to be done using the replication protocol
and pg_basebackup. With this commit it's now possible to make them using
pg_start_backup/pg_stop_backup as well, as long as the backup program can
maintain a persistent connection to the database.

Doing this, backup_label and tablespace_map are returned as results from
pg_stop_backup() instead of being written to the data directory. This makes
the server safe from a crash during an ongoing backup, which can be a problem
with exclusive backups.

The old syntax of the functions remain and work exactly as before, but since the
new syntax is safer this should eventually be deprecated and removed.

Only reference documentation is included. The main section on backup still needs
to be rewritten to cover this, but since that is already scheduled for a separate
large rewrite, it's not included in this patch.

Reviewed by David Steele and Amit Kapila
This commit is contained in:
Magnus Hagander 2016-04-05 20:03:49 +02:00
parent 9457b591b9
commit 7117685461
9 changed files with 265 additions and 53 deletions

View File

@ -17478,7 +17478,7 @@ SELECT set_config('log_statement_stats', 'off', false);
</row>
<row>
<entry>
<literal><function>pg_start_backup(<parameter>label</> <type>text</> <optional>, <parameter>fast</> <type>boolean</> </optional>)</function></literal>
<literal><function>pg_start_backup(<parameter>label</> <type>text</> <optional>, <parameter>fast</> <type>boolean</> <optional>, <parameter>exclusive</> <type>boolean</> </optional></optional>)</function></literal>
</entry>
<entry><type>pg_lsn</type></entry>
<entry>Prepare for performing on-line backup (restricted to superusers or replication roles)</entry>
@ -17488,7 +17488,14 @@ SELECT set_config('log_statement_stats', 'off', false);
<literal><function>pg_stop_backup()</function></literal>
</entry>
<entry><type>pg_lsn</type></entry>
<entry>Finish performing on-line backup (restricted to superusers or replication roles)</entry>
<entry>Finish performing exclusive on-line backup (restricted to superusers or replication roles)</entry>
</row>
<row>
<entry>
<literal><function>pg_stop_backup(<parameter>exclusive</> <type>boolean</>)</function></literal>
</entry>
<entry><type>setof record</type></entry>
<entry>Finish performing exclusive or non-exclusive on-line backup (restricted to superusers or replication roles)</entry>
</row>
<row>
<entry>
@ -17537,15 +17544,19 @@ SELECT set_config('log_statement_stats', 'off', false);
</table>
<para>
<function>pg_start_backup</> accepts an
arbitrary user-defined label for the backup. (Typically this would be
the name under which the backup dump file will be stored.) The function
writes a backup label file (<filename>backup_label</>) and, if there
are any links in the <filename>pg_tblspc/</> directory, a tablespace map
file (<filename>tablespace_map</>) into the database cluster's data
directory, performs a checkpoint, and then returns the backup's starting
transaction log location as text. The user can ignore this result value,
but it is provided in case it is useful.
<function>pg_start_backup</> accepts an arbitrary user-defined label for
the backup. (Typically this would be the name under which the backup dump
file will be stored.) When used in exclusive mode, the function writes a
backup label file (<filename>backup_label</>) and, if there are any links
in the <filename>pg_tblspc/</> directory, a tablespace map file
(<filename>tablespace_map</>) into the database cluster's data directory,
performs a checkpoint, and then returns the backup's starting transaction
log location as text. The user can ignore this result value, but it is
provided in case it is useful. When used in non-exclusive mode, the
contents of these files are instead returned by the
<function>pg_stop_backup</> function, and should be written to the backup
by the caller.
<programlisting>
postgres=# select pg_start_backup('label_goes_here');
pg_start_backup
@ -17560,10 +17571,17 @@ postgres=# select pg_start_backup('label_goes_here');
</para>
<para>
<function>pg_stop_backup</> removes the label file and, if it exists,
the <filename>tablespace_map</> file created by
<function>pg_start_backup</>, and creates a backup history file in
the transaction log archive area. The history file includes the label given to
In an exclusive backup, <function>pg_stop_backup</> removes the label file
and, if it exists, the <filename>tablespace_map</> file created by
<function>pg_start_backup</>. In a non-exclusive backup, the contents of
the <filename>backup_label</> and <filename>tablespace_map</> are returned
in the result of the function, and should be written to files in the
backup (and not in the data directory).
</para>
<para>
The function also creates a backup history file in the transaction log
archive area. The history file includes the label given to
<function>pg_start_backup</>, the starting and ending transaction log locations for
the backup, and the starting and ending times of the backup. The return
value is the backup's ending transaction log location (which again

View File

@ -9768,8 +9768,8 @@ XLogFileNameP(TimeLineID tli, XLogSegNo segno)
*/
XLogRecPtr
do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
char **labelfile, DIR *tblspcdir, List **tablespaces,
char **tblspcmapfile, bool infotbssize,
StringInfo labelfile, DIR *tblspcdir, List **tablespaces,
StringInfo tblspcmapfile, bool infotbssize,
bool needtblspcmapfile)
{
bool exclusive = (labelfile == NULL);
@ -9783,8 +9783,6 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
XLogSegNo _logSegNo;
struct stat stat_buf;
FILE *fp;
StringInfoData labelfbuf;
StringInfoData tblspc_mapfbuf;
backup_started_in_recovery = RecoveryInProgress();
@ -9981,7 +9979,8 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
/*
* Construct tablespace_map file
*/
initStringInfo(&tblspc_mapfbuf);
if (exclusive)
tblspcmapfile = makeStringInfo();
datadirpathlen = strlen(DataDir);
@ -10054,7 +10053,7 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
if (tablespaces)
*tablespaces = lappend(*tablespaces, ti);
appendStringInfo(&tblspc_mapfbuf, "%s %s\n", ti->oid, ti->path);
appendStringInfo(tblspcmapfile, "%s %s\n", ti->oid, ti->path);
pfree(buflinkpath.data);
#else
@ -10073,23 +10072,24 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
/*
* Construct backup label file
*/
initStringInfo(&labelfbuf);
if (exclusive)
labelfile = makeStringInfo();
/* Use the log timezone here, not the session timezone */
stamp_time = (pg_time_t) time(NULL);
pg_strftime(strfbuf, sizeof(strfbuf),
"%Y-%m-%d %H:%M:%S %Z",
pg_localtime(&stamp_time, log_timezone));
appendStringInfo(&labelfbuf, "START WAL LOCATION: %X/%X (file %s)\n",
appendStringInfo(labelfile, "START WAL LOCATION: %X/%X (file %s)\n",
(uint32) (startpoint >> 32), (uint32) startpoint, xlogfilename);
appendStringInfo(&labelfbuf, "CHECKPOINT LOCATION: %X/%X\n",
appendStringInfo(labelfile, "CHECKPOINT LOCATION: %X/%X\n",
(uint32) (checkpointloc >> 32), (uint32) checkpointloc);
appendStringInfo(&labelfbuf, "BACKUP METHOD: %s\n",
appendStringInfo(labelfile, "BACKUP METHOD: %s\n",
exclusive ? "pg_start_backup" : "streamed");
appendStringInfo(&labelfbuf, "BACKUP FROM: %s\n",
appendStringInfo(labelfile, "BACKUP FROM: %s\n",
backup_started_in_recovery ? "standby" : "master");
appendStringInfo(&labelfbuf, "START TIME: %s\n", strfbuf);
appendStringInfo(&labelfbuf, "LABEL: %s\n", backupidstr);
appendStringInfo(labelfile, "START TIME: %s\n", strfbuf);
appendStringInfo(labelfile, "LABEL: %s\n", backupidstr);
/*
* Okay, write the file, or return its contents to caller.
@ -10123,7 +10123,7 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
(errcode_for_file_access(),
errmsg("could not create file \"%s\": %m",
BACKUP_LABEL_FILE)));
if (fwrite(labelfbuf.data, labelfbuf.len, 1, fp) != 1 ||
if (fwrite(labelfile->data, labelfile->len, 1, fp) != 1 ||
fflush(fp) != 0 ||
pg_fsync(fileno(fp)) != 0 ||
ferror(fp) ||
@ -10132,10 +10132,12 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
(errcode_for_file_access(),
errmsg("could not write file \"%s\": %m",
BACKUP_LABEL_FILE)));
pfree(labelfbuf.data);
/* Allocated locally for exclusive backups, so free separately */
pfree(labelfile->data);
pfree(labelfile);
/* Write backup tablespace_map file. */
if (tblspc_mapfbuf.len > 0)
if (tblspcmapfile->len > 0)
{
if (stat(TABLESPACE_MAP, &stat_buf) != 0)
{
@ -10159,7 +10161,7 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
(errcode_for_file_access(),
errmsg("could not create file \"%s\": %m",
TABLESPACE_MAP)));
if (fwrite(tblspc_mapfbuf.data, tblspc_mapfbuf.len, 1, fp) != 1 ||
if (fwrite(tblspcmapfile->data, tblspcmapfile->len, 1, fp) != 1 ||
fflush(fp) != 0 ||
pg_fsync(fileno(fp)) != 0 ||
ferror(fp) ||
@ -10170,13 +10172,9 @@ do_pg_start_backup(const char *backupidstr, bool fast, TimeLineID *starttli_p,
TABLESPACE_MAP)));
}
pfree(tblspc_mapfbuf.data);
}
else
{
*labelfile = labelfbuf.data;
if (tblspc_mapfbuf.len > 0)
*tblspcmapfile = tblspc_mapfbuf.data;
/* Allocated locally for exclusive backups, so free separately */
pfree(tblspcmapfile->data);
pfree(tblspcmapfile);
}
}
PG_END_ENSURE_ERROR_CLEANUP(pg_start_backup_callback, (Datum) BoolGetDatum(exclusive));
@ -10283,7 +10281,16 @@ do_pg_stop_backup(char *labelfile, bool waitforarchive, TimeLineID *stoptli_p)
*/
WALInsertLockAcquireExclusive();
if (exclusive)
{
if (!XLogCtl->Insert.exclusiveBackup)
{
WALInsertLockRelease();
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("exclusive backup not in progress")));
}
XLogCtl->Insert.exclusiveBackup = false;
}
else
{
/*

View File

@ -28,13 +28,36 @@
#include "replication/walreceiver.h"
#include "storage/smgr.h"
#include "utils/builtins.h"
#include "utils/memutils.h"
#include "utils/numeric.h"
#include "utils/guc.h"
#include "utils/pg_lsn.h"
#include "utils/timestamp.h"
#include "utils/tuplestore.h"
#include "storage/fd.h"
#include "storage/ipc.h"
/*
* Store label file and tablespace map during non-exclusive backups.
*/
static StringInfo label_file;
static StringInfo tblspc_map_file;
static bool exclusive_backup_running = false;
static bool nonexclusive_backup_running = false;
/*
* Called when the backend exits with a running non-exclusive base backup,
* to clean up state.
*/
static void
nonexclusive_base_backup_cleanup(int code, Datum arg)
{
do_pg_abort_backup();
ereport(WARNING,
(errmsg("aborting backup due to backend exiting before pg_stop_backup was called")));
}
/*
* pg_start_backup: set up for taking an on-line backup dump
*
@ -49,6 +72,7 @@ pg_start_backup(PG_FUNCTION_ARGS)
{
text *backupid = PG_GETARG_TEXT_P(0);
bool fast = PG_GETARG_BOOL(1);
bool exclusive = PG_GETARG_BOOL(2);
char *backupidstr;
XLogRecPtr startpoint;
DIR *dir;
@ -60,14 +84,42 @@ pg_start_backup(PG_FUNCTION_ARGS)
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("must be superuser or replication role to run a backup")));
if (exclusive_backup_running || nonexclusive_backup_running)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("a backup is already in progress in this session")));
/* Make sure we can open the directory with tablespaces in it */
dir = AllocateDir("pg_tblspc");
if (!dir)
ereport(ERROR,
(errmsg("could not open directory \"%s\": %m", "pg_tblspc")));
startpoint = do_pg_start_backup(backupidstr, fast, NULL, NULL,
dir, NULL, NULL, false, true);
if (exclusive)
{
startpoint = do_pg_start_backup(backupidstr, fast, NULL, NULL,
dir, NULL, NULL, false, true);
exclusive_backup_running = true;
}
else
{
MemoryContext oldcontext;
/*
* Label file and tablespace map file need to be long-lived, since they
* are read in pg_stop_backup.
*/
oldcontext = MemoryContextSwitchTo(TopMemoryContext);
label_file = makeStringInfo();
tblspc_map_file = makeStringInfo();
MemoryContextSwitchTo(oldcontext);
startpoint = do_pg_start_backup(backupidstr, fast, NULL, label_file,
dir, NULL, tblspc_map_file, false, true);
nonexclusive_backup_running = true;
before_shmem_exit(nonexclusive_base_backup_cleanup, (Datum) 0);
}
FreeDir(dir);
@ -86,6 +138,10 @@ pg_start_backup(PG_FUNCTION_ARGS)
* record for that and the file is for informational and debug purposes only.
*
* Note: different from CancelBackup which just cancels online backup mode.
*
* Note: this version is only called to stop an exclusive backup. The function
* pg_stop_backup_v2 (overloaded as pg_stop_backup in SQL) is called to
* stop non-exclusive backups.
*/
Datum
pg_stop_backup(PG_FUNCTION_ARGS)
@ -97,11 +153,136 @@ pg_stop_backup(PG_FUNCTION_ARGS)
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser or replication role to run a backup"))));
if (nonexclusive_backup_running)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("non-exclusive backup in progress"),
errhint("did you mean to use pg_stop_backup('f')?")));
/*
* Exclusive backups were typically started in a different connection,
* so don't try to verify that exclusive_backup_running is set in this one.
* Actual verification that an exclusive backup is in fact running is handled
* inside do_pg_stop_backup.
*/
stoppoint = do_pg_stop_backup(NULL, true, NULL);
exclusive_backup_running = false;
PG_RETURN_LSN(stoppoint);
}
/*
* pg_stop_backup_v2: finish taking exclusive or nonexclusive on-line backup.
*
* Works the same as pg_stop_backup, except for non-exclusive backups it returns
* the backup label and tablespace map files as text fields in as part of the
* resultset.
*/
Datum
pg_stop_backup_v2(PG_FUNCTION_ARGS)
{
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
TupleDesc tupdesc;
Tuplestorestate *tupstore;
MemoryContext per_query_ctx;
MemoryContext oldcontext;
Datum values[3];
bool nulls[3];
bool exclusive = PG_GETARG_BOOL(0);
XLogRecPtr stoppoint;
/* check to see if caller supports us returning a tuplestore */
if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that cannot accept a set")));
if (!(rsinfo->allowedModes & SFRM_Materialize))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("materialize mode required, but it is not " \
"allowed in this context")));
if (!superuser() && !has_rolreplication(GetUserId()))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser or replication role to run a backup"))));
/* Build a tuple descriptor for our result type */
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
elog(ERROR, "return type must be a row type");
per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
oldcontext = MemoryContextSwitchTo(per_query_ctx);
tupstore = tuplestore_begin_heap(true, false, work_mem);
rsinfo->returnMode = SFRM_Materialize;
rsinfo->setResult = tupstore;
rsinfo->setDesc = tupdesc;
MemoryContextSwitchTo(oldcontext);
MemSet(values, 0, sizeof(values));
MemSet(nulls, 0, sizeof(nulls));
if (exclusive)
{
if (nonexclusive_backup_running)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("non-exclusive backup in progress"),
errhint("did you mean to use pg_stop_backup('f')?")));
/*
* Stop the exclusive backup, and since we're in an exclusive backup
* return NULL for both backup_label and tablespace_map.
*/
stoppoint = do_pg_stop_backup(NULL, true, NULL);
exclusive_backup_running = false;
nulls[1] = true;
nulls[2] = true;
}
else
{
if (!nonexclusive_backup_running)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("non-exclusive backup is not in progress"),
errhint("did you mean to use pg_stop_backup('t')?")));
/*
* Stop the non-exclusive backup. Return a copy of the backup
* label and tablespace map so they can be written to disk by
* the caller.
*/
stoppoint = do_pg_stop_backup(label_file->data, true, NULL);
nonexclusive_backup_running = false;
cancel_before_shmem_exit(nonexclusive_base_backup_cleanup, (Datum) 0);
values[1] = CStringGetTextDatum(label_file->data);
values[2] = CStringGetTextDatum(tblspc_map_file->data);
/* Free structures allocated in TopMemoryContext */
pfree(label_file->data);
pfree(label_file);
label_file = NULL;
pfree(tblspc_map_file->data);
pfree(tblspc_map_file);
tblspc_map_file = NULL;
}
/* Stoppoint is included on both exclusive and nonexclusive backups */
values[0] = LSNGetDatum(stoppoint);
tuplestore_putvalues(tupstore, tupdesc, values, nulls);
tuplestore_donestoring(typstore);
return (Datum) 0;
}
/*
* pg_switch_xlog: switch to next xlog file
*/

View File

@ -921,7 +921,7 @@ COMMENT ON FUNCTION ts_debug(text) IS
--
CREATE OR REPLACE FUNCTION
pg_start_backup(label text, fast boolean DEFAULT false)
pg_start_backup(label text, fast boolean DEFAULT false, exclusive boolean DEFAULT true)
RETURNS pg_lsn STRICT VOLATILE LANGUAGE internal AS 'pg_start_backup';
-- legacy definition for compatibility with 9.3

View File

@ -117,8 +117,8 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
TimeLineID starttli;
XLogRecPtr endptr;
TimeLineID endtli;
char *labelfile;
char *tblspc_map_file = NULL;
StringInfo labelfile;
StringInfo tblspc_map_file = NULL;
int datadirpathlen;
List *tablespaces = NIL;
@ -126,9 +126,12 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
backup_started_in_recovery = RecoveryInProgress();
labelfile = makeStringInfo();
tblspc_map_file = makeStringInfo();
startptr = do_pg_start_backup(opt->label, opt->fastcheckpoint, &starttli,
&labelfile, tblspcdir, &tablespaces,
&tblspc_map_file,
labelfile, tblspcdir, &tablespaces,
tblspc_map_file,
opt->progress, opt->sendtblspcmapfile);
/*
@ -206,7 +209,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
struct stat statbuf;
/* In the main tar, include the backup_label first... */
sendFileWithContent(BACKUP_LABEL_FILE, labelfile);
sendFileWithContent(BACKUP_LABEL_FILE, labelfile->data);
/*
* Send tablespace_map file if required and then the bulk of
@ -214,7 +217,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
*/
if (tblspc_map_file && opt->sendtblspcmapfile)
{
sendFileWithContent(TABLESPACE_MAP, tblspc_map_file);
sendFileWithContent(TABLESPACE_MAP, tblspc_map_file->data);
sendDir(".", 1, false, tablespaces, false);
}
else
@ -247,7 +250,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
}
PG_END_ENSURE_ERROR_CLEANUP(base_backup_cleanup, (Datum) 0);
endptr = do_pg_stop_backup(labelfile, !opt->nowait, &endtli);
endptr = do_pg_stop_backup(labelfile->data, !opt->nowait, &endtli);
if (opt->includewal)
{

View File

@ -276,8 +276,8 @@ extern void assign_checkpoint_completion_target(double newval, void *extra);
* Starting/stopping a base backup
*/
extern XLogRecPtr do_pg_start_backup(const char *backupidstr, bool fast,
TimeLineID *starttli_p, char **labelfile, DIR *tblspcdir,
List **tablespaces, char **tblspcmapfile, bool infotbssize,
TimeLineID *starttli_p, StringInfo labelfile, DIR *tblspcdir,
List **tablespaces, StringInfo tblspcmapfile, bool infotbssize,
bool needtblspcmapfile);
extern XLogRecPtr do_pg_stop_backup(char *labelfile, bool waitforarchive,
TimeLineID *stoptli_p);

View File

@ -15,6 +15,7 @@
extern Datum pg_start_backup(PG_FUNCTION_ARGS);
extern Datum pg_stop_backup(PG_FUNCTION_ARGS);
extern Datum pg_stop_backup_v2(PG_FUNCTION_ARGS);
extern Datum pg_switch_xlog(PG_FUNCTION_ARGS);
extern Datum pg_create_restore_point(PG_FUNCTION_ARGS);
extern Datum pg_current_xlog_location(PG_FUNCTION_ARGS);

View File

@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 201603301
#define CATALOG_VERSION_NO 201604051
#endif

View File

@ -3075,10 +3075,12 @@ DATA(insert OID = 2171 ( pg_cancel_backend PGNSP PGUID 12 1 0 0 0 f f f f t f v
DESCR("cancel a server process' current query");
DATA(insert OID = 2096 ( pg_terminate_backend PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 16 "23" _null_ _null_ _null_ _null_ _null_ pg_terminate_backend _null_ _null_ _null_ ));
DESCR("terminate a server process");
DATA(insert OID = 2172 ( pg_start_backup PGNSP PGUID 12 1 0 0 0 f f f f t f v s 2 0 3220 "25 16" _null_ _null_ _null_ _null_ _null_ pg_start_backup _null_ _null_ _null_ ));
DATA(insert OID = 2172 ( pg_start_backup PGNSP PGUID 12 1 0 0 0 f f f f t f v s 3 0 3220 "25 16 16" _null_ _null_ _null_ _null_ _null_ pg_start_backup _null_ _null_ _null_ ));
DESCR("prepare for taking an online backup");
DATA(insert OID = 2173 ( pg_stop_backup PGNSP PGUID 12 1 0 0 0 f f f f t f v s 0 0 3220 "" _null_ _null_ _null_ _null_ _null_ pg_stop_backup _null_ _null_ _null_ ));
DESCR("finish taking an online backup");
DATA(insert OID = 2739 ( pg_stop_backup PGNSP PGUID 12 1 1 0 0 f f f f t t v s 1 0 2249 "16" "{16,3220,25,25}" "{i,o,o,o}" "{exclusive,lsn,labelfile,spcmapfile}" _null_ _null_ pg_stop_backup_v2 _null_ _null_ _null_ ));
DESCR("finish taking an online backup");
DATA(insert OID = 3813 ( pg_is_in_backup PGNSP PGUID 12 1 0 0 0 f f f f t f v s 0 0 16 "" _null_ _null_ _null_ _null_ _null_ pg_is_in_backup _null_ _null_ _null_ ));
DESCR("true if server is in online backup");
DATA(insert OID = 3814 ( pg_backup_start_time PGNSP PGUID 12 1 0 0 0 f f f f t f s s 0 0 1184 "" _null_ _null_ _null_ _null_ _null_ pg_backup_start_time _null_ _null_ _null_ ));