diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 709836f2be75a27e4b3c4210a4ea62faf8904c3d..a776be2badb943c7e7b503ef204047bddaacea69 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.317 2008/08/11 11:05:10 heikki Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.318 2008/09/08 16:42:15 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -391,7 +391,8 @@ static bool InRedo = false;
static void XLogArchiveNotify(const char *xlog);
static void XLogArchiveNotifySeg(uint32 log, uint32 seg);
-static bool XLogArchiveCheckDone(const char *xlog, bool create_if_missing);
+static bool XLogArchiveCheckDone(const char *xlog);
+static bool XLogArchiveIsBusy(const char *xlog);
static void XLogArchiveCleanup(const char *xlog);
static void readRecoveryCommandFile(void);
static void exitArchiveRecovery(TimeLineID endTLI,
@@ -1137,7 +1138,7 @@ XLogArchiveNotifySeg(uint32 log, uint32 seg)
* create <XLOG>.ready fails, we'll retry during subsequent checkpoints.
*/
static bool
-XLogArchiveCheckDone(const char *xlog, bool create_if_missing)
+XLogArchiveCheckDone(const char *xlog)
{
char archiveStatusPath[MAXPGPATH];
struct stat stat_buf;
@@ -1162,12 +1163,54 @@ XLogArchiveCheckDone(const char *xlog, bool create_if_missing)
return true;
/* Retry creation of the .ready file */
- if (create_if_missing)
- XLogArchiveNotify(xlog);
-
+ XLogArchiveNotify(xlog);
return false;
}
+/*
+ * XLogArchiveIsBusy
+ *
+ * Check to see if an XLOG segment file is still unarchived.
+ * This is almost but not quite the inverse of XLogArchiveCheckDone: in
+ * the first place we aren't chartered to recreate the .ready file, and
+ * in the second place we should consider that if the file is already gone
+ * then it's not busy. (This check is needed to handle the race condition
+ * that a checkpoint already deleted the no-longer-needed file.)
+ */
+static bool
+XLogArchiveIsBusy(const char *xlog)
+{
+ char archiveStatusPath[MAXPGPATH];
+ struct stat stat_buf;
+
+ /* First check for .done --- this means archiver is done with it */
+ StatusFilePath(archiveStatusPath, xlog, ".done");
+ if (stat(archiveStatusPath, &stat_buf) == 0)
+ return false;
+
+ /* check for .ready --- this means archiver is still busy with it */
+ StatusFilePath(archiveStatusPath, xlog, ".ready");
+ if (stat(archiveStatusPath, &stat_buf) == 0)
+ return true;
+
+ /* Race condition --- maybe archiver just finished, so recheck */
+ StatusFilePath(archiveStatusPath, xlog, ".done");
+ if (stat(archiveStatusPath, &stat_buf) == 0)
+ return false;
+
+ /*
+ * Check to see if the WAL file has been removed by checkpoint,
+ * which implies it has already been archived, and explains why we
+ * can't see a status file for it.
+ */
+ snprintf(archiveStatusPath, MAXPGPATH, XLOGDIR "/%s", xlog);
+ if (stat(archiveStatusPath, &stat_buf) != 0 &&
+ errno == ENOENT)
+ return false;
+
+ return true;
+}
+
/*
* XLogArchiveCleanup
*
@@ -2499,14 +2542,14 @@ RestoreArchivedFile(char *path, const char *xlogfname,
*
* We initialise this with the filename of an InvalidXLogRecPtr, which
* will prevent the deletion of any WAL files from the archive
- * because of the alphabetic sorting property of WAL filenames.
+ * because of the alphabetic sorting property of WAL filenames.
*
* Once we have successfully located the redo pointer of the checkpoint
* from which we start recovery we never request a file prior to the redo
* pointer of the last restartpoint. When redo begins we know that we
* have successfully located it, so there is no need for additional
* status flags to signify the point when we can begin deleting WAL files
- * from the archive.
+ * from the archive.
*/
if (InRedo)
{
@@ -2740,7 +2783,7 @@ RemoveOldXlogFiles(uint32 log, uint32 seg, XLogRecPtr endptr)
strspn(xlde->d_name, "0123456789ABCDEF") == 24 &&
strcmp(xlde->d_name + 8, lastoff + 8) <= 0)
{
- if (XLogArchiveCheckDone(xlde->d_name, true))
+ if (XLogArchiveCheckDone(xlde->d_name))
{
snprintf(path, MAXPGPATH, XLOGDIR "/%s", xlde->d_name);
@@ -2807,7 +2850,7 @@ CleanupBackupHistory(void)
strcmp(xlde->d_name + strlen(xlde->d_name) - strlen(".backup"),
".backup") == 0)
{
- if (XLogArchiveCheckDone(xlde->d_name, true))
+ if (XLogArchiveCheckDone(xlde->d_name))
{
ereport(DEBUG2,
(errmsg("removing transaction log backup history file \"%s\"",
@@ -6623,6 +6666,12 @@ pg_stop_backup(PG_FUNCTION_ARGS)
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to run a backup"))));
+ if (!XLogArchivingActive())
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("WAL archiving is not active"),
+ errhint("archive_mode must be enabled at server start.")));
+
/*
* OK to clear forcePageWrites
*/
@@ -6721,17 +6770,14 @@ pg_stop_backup(PG_FUNCTION_ARGS)
CleanupBackupHistory();
/*
- * Wait until the history file has been archived. We assume that the
- * alphabetic sorting property of the WAL files ensures the last WAL
- * file is guaranteed archived by the time the history file is archived.
+ * Wait until both the last WAL file filled during backup and the history
+ * file have been archived. We assume that the alphabetic sorting
+ * property of the WAL files ensures any earlier WAL files are safely
+ * archived as well.
*
* We wait forever, since archive_command is supposed to work and
- * we assume the admin wanted his backup to work completely. If you
- * don't wish to wait, you can SET statement_timeout = xx;
- *
- * If the status file is missing, we assume that is because it was
- * set to .ready before we slept, then while asleep it has been set
- * to .done and then removed by a concurrent checkpoint.
+ * we assume the admin wanted his backup to work completely. If you
+ * don't wish to wait, you can set statement_timeout.
*/
BackupHistoryFileName(histfilepath, ThisTimeLineID, _logId, _logSeg,
startpoint.xrecoff % XLogSegSize);
@@ -6739,7 +6785,8 @@ pg_stop_backup(PG_FUNCTION_ARGS)
seconds_before_warning = 60;
waits = 0;
- while (!XLogArchiveCheckDone(histfilepath, false))
+ while (XLogArchiveIsBusy(stopxlogfilename) ||
+ XLogArchiveIsBusy(histfilepath))
{
CHECK_FOR_INTERRUPTS();
@@ -6748,8 +6795,9 @@ pg_stop_backup(PG_FUNCTION_ARGS)
if (++waits >= seconds_before_warning)
{
seconds_before_warning *= 2; /* This wraps in >10 years... */
- elog(WARNING, "pg_stop_backup() waiting for archive to complete "
- "(%d seconds delay)", waits);
+ ereport(WARNING,
+ (errmsg("pg_stop_backup still waiting for archive to complete (%d seconds elapsed)",
+ waits)));
}
}