* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.115 2003/05/10 18:01:31 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.116 2003/05/22 14:39:28 tgl Exp $
*
*-------------------------------------------------------------------------
*/
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
- ThisStartUpID = checkPoint.ThisStartUpID;
+ /*
+ * If it was a shutdown checkpoint, then any following WAL entries were
+ * created under the next StartUpID; if it was a regular checkpoint then
+ * any following WAL entries were created under the same StartUpID.
+ * We must replay WAL entries using the same StartUpID they were created
+ * under, so temporarily adopt that SUI (see also xlog_redo()).
+ */
+ if (wasShutdown)
+ ThisStartUpID = checkPoint.ThisStartUpID + 1;
+ else
+ ThisStartUpID = checkPoint.ThisStartUpID;
+
RedoRecPtr = XLogCtl->Insert.RedoRecPtr =
XLogCtl->SavedRedoRecPtr = checkPoint.redo;
ControlFile->logSeg = openLogSeg + 1;
Insert = &XLogCtl->Insert;
Insert->PrevRecord = LastRec;
+ XLogCtl->xlblocks[0].xlogid = openLogId;
+ XLogCtl->xlblocks[0].xrecoff =
+ ((EndOfLog.xrecoff - 1) / BLCKSZ + 1) * BLCKSZ;
/*
- * If the next record will go to the new page then initialize for that
- * one.
+ * Tricky point here: readBuf contains the *last* block that the
+ * LastRec record spans, not the one it starts in. The last block
+ * is indeed the one we want to use.
*/
- if ((BLCKSZ - EndOfLog.xrecoff % BLCKSZ) < SizeOfXLogRecord)
- EndOfLog.xrecoff += (BLCKSZ - EndOfLog.xrecoff % BLCKSZ);
- if (EndOfLog.xrecoff % BLCKSZ == 0)
- {
- XLogRecPtr NewPageEndPtr;
-
- NewPageEndPtr = EndOfLog;
- if (NewPageEndPtr.xrecoff >= XLogFileSize)
- {
- /* crossing a logid boundary */
- NewPageEndPtr.xlogid += 1;
- NewPageEndPtr.xrecoff = BLCKSZ;
- }
- else
- NewPageEndPtr.xrecoff += BLCKSZ;
- XLogCtl->xlblocks[0] = NewPageEndPtr;
- Insert->currpage->xlp_magic = XLOG_PAGE_MAGIC;
- if (InRecovery)
- Insert->currpage->xlp_sui = ThisStartUpID;
- else
- Insert->currpage->xlp_sui = ThisStartUpID + 1;
- Insert->currpage->xlp_pageaddr.xlogid = NewPageEndPtr.xlogid;
- Insert->currpage->xlp_pageaddr.xrecoff = NewPageEndPtr.xrecoff - BLCKSZ;
- /* rest of buffer was zeroed in XLOGShmemInit */
- Insert->currpos = (char *) Insert->currpage + SizeOfXLogPHD;
- }
- else
- {
- XLogCtl->xlblocks[0].xlogid = openLogId;
- XLogCtl->xlblocks[0].xrecoff =
- ((EndOfLog.xrecoff - 1) / BLCKSZ + 1) * BLCKSZ;
-
- /*
- * Tricky point here: readBuf contains the *last* block that the
- * LastRec record spans, not the one it starts in. The last block
- * is indeed the one we want to use.
- */
- Assert(readOff == (XLogCtl->xlblocks[0].xrecoff - BLCKSZ) % XLogSegSize);
- memcpy((char *) Insert->currpage, readBuf, BLCKSZ);
- Insert->currpos = (char *) Insert->currpage +
- (EndOfLog.xrecoff + BLCKSZ - XLogCtl->xlblocks[0].xrecoff);
- /* Make sure rest of page is zero */
- memset(Insert->currpos, 0, INSERT_FREESPACE(Insert));
- }
+ Assert(readOff == (XLogCtl->xlblocks[0].xrecoff - BLCKSZ) % XLogSegSize);
+ memcpy((char *) Insert->currpage, readBuf, BLCKSZ);
+ Insert->currpos = (char *) Insert->currpage +
+ (EndOfLog.xrecoff + BLCKSZ - XLogCtl->xlblocks[0].xrecoff);
+ /* Make sure rest of page is zero */
+ MemSet(Insert->currpos, 0, INSERT_FREESPACE(Insert));
LogwrtResult.Write = LogwrtResult.Flush = EndOfLog;
MyXactMadeTempRelUpdate = false;
/*
+ * At this point, ThisStartUpID is the largest SUI that we could
+ * find evidence for in the WAL entries. But check it against
+ * pg_control's latest checkpoint, to make sure that we can't
+ * accidentally re-use an already-used SUI.
+ */
+ if (ThisStartUpID < ControlFile->checkPointCopy.ThisStartUpID)
+ ThisStartUpID = ControlFile->checkPointCopy.ThisStartUpID;
+
+ /*
* Perform a new checkpoint to update our recovery activity to disk.
*
+ * Note that we write a shutdown checkpoint. This is correct since
+ * the records following it will use SUI one more than what is shown
+ * in the checkpoint's ThisStartUpID.
+ *
* In case we had to use the secondary checkpoint, make sure that
* it will still be shown as the secondary checkpoint after this
* CreateCheckPoint operation; we don't want the broken primary
*/
XLogCloseRelationCache();
}
+ else
+ {
+ /*
+ * If we are not doing recovery, then we saw a checkpoint with nothing
+ * after it, and we can safely use StartUpID equal to one more than
+ * the checkpoint's SUI. But just for paranoia's sake, check against
+ * pg_control too.
+ */
+ ThisStartUpID = checkPoint.ThisStartUpID;
+ if (ThisStartUpID < ControlFile->checkPointCopy.ThisStartUpID)
+ ThisStartUpID = ControlFile->checkPointCopy.ThisStartUpID;
+ }
/*
* Preallocate additional log files, if wanted.
*/
PreallocXlogFiles(EndOfLog);
+ /*
+ * Advance StartUpID to one more than the highest value used previously.
+ */
+ ThisStartUpID++;
+ XLogCtl->ThisStartUpID = ThisStartUpID;
+
+ /*
+ * Okay, we're officially UP.
+ */
InRecovery = false;
ControlFile->state = DB_IN_PRODUCTION;
ControlFile->time = time(NULL);
UpdateControlFile();
- ThisStartUpID++;
- XLogCtl->ThisStartUpID = ThisStartUpID;
-
/* Start up the commit log, too */
StartupCLOG();
UpdateControlFile();
}
- memset(&checkPoint, 0, sizeof(checkPoint));
+ MemSet(&checkPoint, 0, sizeof(checkPoint));
checkPoint.ThisStartUpID = ThisStartUpID;
checkPoint.time = time(NULL);
ShmemVariableCache->nextXid = checkPoint.nextXid;
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
+ /* Any later WAL records should be run with shutdown SUI plus 1 */
+ ThisStartUpID = checkPoint.ThisStartUpID + 1;
}
else if (info == XLOG_CHECKPOINT_ONLINE)
{
ShmemVariableCache->nextOid = checkPoint.nextOid;
ShmemVariableCache->oidCount = 0;
}
+ /* Any later WAL records should be run with the then-active SUI */
+ ThisStartUpID = checkPoint.ThisStartUpID;
}
}