</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>
<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>
</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
</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
*/
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);
XLogSegNo _logSegNo;
struct stat stat_buf;
FILE *fp;
- StringInfoData labelfbuf;
- StringInfoData tblspc_mapfbuf;
backup_started_in_recovery = RecoveryInProgress();
/*
* Construct tablespace_map file
*/
- initStringInfo(&tblspc_mapfbuf);
+ if (exclusive)
+ tblspcmapfile = makeStringInfo();
datadirpathlen = strlen(DataDir);
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
/*
* 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.
(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) ||
(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)
{
(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) ||
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));
*/
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
{
/*
#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
*
{
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;
(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);
* 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)
(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
*/
--
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
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;
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);
/*
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
*/
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
}
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)
{
* 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);
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);
*/
/* yyyymmddN */
-#define CATALOG_VERSION_NO 201603301
+#define CATALOG_VERSION_NO 201604051
#endif
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_ ));
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