Remove undo information from pg_controldata --- never used.

Florian G. Pflug

src/backend/access/transam/xlog.c

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.264 2007/02/14 05:00:40 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.265 2007/03/03 20:02:26 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -4039,7 +4039,6 @@ BootStrapXLOG(void)
 	/* Set up information for the initial checkpoint record */
 	checkPoint.redo.xlogid = 0;
 	checkPoint.redo.xrecoff = SizeOfXLogLongPHD;
-	checkPoint.undo = checkPoint.redo;
 	checkPoint.ThisTimeLineID = ThisTimeLineID;
 	checkPoint.nextXidEpoch = 0;
 	checkPoint.nextXid = FirstNormalTransactionId;
@@ -4698,9 +4697,8 @@ StartupXLOG(void)
 	wasShutdown = (record->xl_info == XLOG_CHECKPOINT_SHUTDOWN);
 
 	ereport(LOG,
-	 (errmsg("redo record is at %X/%X; undo record is at %X/%X; shutdown %s",
+	 (errmsg("redo record is at %X/%X; shutdown %s",
 			 checkPoint.redo.xlogid, checkPoint.redo.xrecoff,
-			 checkPoint.undo.xlogid, checkPoint.undo.xrecoff,
 			 wasShutdown ? "TRUE" : "FALSE")));
 	ereport(LOG,
 			(errmsg("next transaction ID: %u/%u; next OID: %u",
@@ -4730,20 +4728,17 @@ StartupXLOG(void)
 	if (XLByteLT(RecPtr, checkPoint.redo))
 		ereport(PANIC,
 				(errmsg("invalid redo in checkpoint record")));
-	if (checkPoint.undo.xrecoff == 0)
-		checkPoint.undo = RecPtr;
 
 	/*
 	 * Check whether we need to force recovery from WAL.  If it appears to
 	 * have been a clean shutdown and we did not have a recovery.conf file,
 	 * then assume no recovery needed.
 	 */
-	if (XLByteLT(checkPoint.undo, RecPtr) ||
-		XLByteLT(checkPoint.redo, RecPtr))
+	if (XLByteLT(checkPoint.redo, RecPtr))
 	{
 		if (wasShutdown)
 			ereport(PANIC,
-				(errmsg("invalid redo/undo record in shutdown checkpoint")));
+				(errmsg("invalid redo record in shutdown checkpoint")));
 		InRecovery = true;
 	}
 	else if (ControlFile->state != DB_SHUTDOWNED)
@@ -5850,10 +5845,9 @@ xlog_desc(StringInfo buf, uint8 xl_info, char *rec)
 	{
 		CheckPoint *checkpoint = (CheckPoint *) rec;
 
-		appendStringInfo(buf, "checkpoint: redo %X/%X; undo %X/%X; "
+		appendStringInfo(buf, "checkpoint: redo %X/%X; "
 						 "tli %u; xid %u/%u; oid %u; multi %u; offset %u; %s",
 						 checkpoint->redo.xlogid, checkpoint->redo.xrecoff,
-						 checkpoint->undo.xlogid, checkpoint->undo.xrecoff,
 						 checkpoint->ThisTimeLineID,
 						 checkpoint->nextXidEpoch, checkpoint->nextXid,
 						 checkpoint->nextOid,

src/bin/pg_controldata/pg_controldata.c

@@ -6,7 +6,7 @@
  * copyright (c) Oliver Elphick <olly@lfix.co.uk>, 2001;
  * licence: BSD
  *
- * $PostgreSQL: pgsql/src/bin/pg_controldata/pg_controldata.c,v 1.32 2006/12/08 19:50:53 tgl Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_controldata/pg_controldata.c,v 1.33 2007/03/03 20:02:27 momjian Exp $
  */
 #include "postgres.h"
 
@@ -168,9 +168,6 @@ main(int argc, char *argv[])
 	printf(_("Latest checkpoint's REDO location:    %X/%X\n"),
 		   ControlFile.checkPointCopy.redo.xlogid,
 		   ControlFile.checkPointCopy.redo.xrecoff);
-	printf(_("Latest checkpoint's UNDO location:    %X/%X\n"),
-		   ControlFile.checkPointCopy.undo.xlogid,
-		   ControlFile.checkPointCopy.undo.xrecoff);
 	printf(_("Latest checkpoint's TimeLineID:       %u\n"),
 		   ControlFile.checkPointCopy.ThisTimeLineID);
 	printf(_("Latest checkpoint's NextXID:          %u/%u\n"),

src/bin/pg_resetxlog/pg_resetxlog.c

@@ -23,7 +23,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.57 2007/02/10 14:58:55 petere Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.58 2007/03/03 20:02:27 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -464,7 +464,6 @@ GuessControlValues(void)
 
 	ControlFile.checkPointCopy.redo.xlogid = 0;
 	ControlFile.checkPointCopy.redo.xrecoff = SizeOfXLogLongPHD;
-	ControlFile.checkPointCopy.undo = ControlFile.checkPointCopy.redo;
 	ControlFile.checkPointCopy.ThisTimeLineID = 1;
 	ControlFile.checkPointCopy.nextXidEpoch = 0;
 	ControlFile.checkPointCopy.nextXid = (TransactionId) 514;	/* XXX */
@@ -600,7 +599,6 @@ RewriteControlFile(void)
 	ControlFile.checkPointCopy.redo.xlogid = newXlogId;
 	ControlFile.checkPointCopy.redo.xrecoff =
 		newXlogSeg * XLogSegSize + SizeOfXLogLongPHD;
-	ControlFile.checkPointCopy.undo = ControlFile.checkPointCopy.redo;
 	ControlFile.checkPointCopy.time = time(NULL);
 
 	ControlFile.state = DB_SHUTDOWNED;

src/include/access/xlog_internal.h

@@ -11,7 +11,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/access/xlog_internal.h,v 1.18 2007/01/05 22:19:51 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/access/xlog_internal.h,v 1.19 2007/03/03 20:02:27 momjian Exp $
  */
 #ifndef XLOG_INTERNAL_H
 #define XLOG_INTERNAL_H
@@ -71,7 +71,7 @@ typedef struct XLogContRecord
 /*
  * Each page of XLOG file has a header like this:
  */
-#define XLOG_PAGE_MAGIC 0xD05E	/* can be used as WAL version indicator */
+#define XLOG_PAGE_MAGIC 0xD05F	/* can be used as WAL version indicator */
 
 typedef struct XLogPageHeaderData
 {

src/include/catalog/pg_control.h

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.35 2007/01/05 22:19:52 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.36 2007/03/03 20:02:27 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -22,7 +22,7 @@
 
 
 /* Version identifier for this pg_control format */
-#define PG_CONTROL_VERSION	831
+#define PG_CONTROL_VERSION	832
 
 /*
  * Body of CheckPoint XLOG records.  This is declared here because we keep
@@ -32,9 +32,6 @@ typedef struct CheckPoint
 {
 	XLogRecPtr	redo;			/* next RecPtr available when we began to
 								 * create CheckPoint (i.e. REDO start point) */
-	XLogRecPtr	undo;			/* first record of oldest in-progress
-								 * transaction when we started (i.e. UNDO end
-								 * point) */
 	TimeLineID	ThisTimeLineID; /* current TLI */
 	uint32		nextXidEpoch;	/* higher-order bits of nextXid */
 	TransactionId nextXid;		/* next free XID */