Index: src/backend/catalog/index.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/catalog/index.c,v
retrieving revision 1.280
diff -c -c -r1.280 index.c
*** src/backend/catalog/index.c	3 Mar 2007 20:08:41 -0000	1.280
--- src/backend/catalog/index.c	23 Mar 2007 19:20:44 -0000
***************
*** 1394,1400 ****
  	}
  	else if (indexInfo->ii_Concurrent)
  	{
! 		snapshot = CopySnapshot(GetTransactionSnapshot());
  		OldestXmin = InvalidTransactionId;		/* not used */
  	}
  	else
--- 1394,1400 ----
  	}
  	else if (indexInfo->ii_Concurrent)
  	{
! 		snapshot = CopySnapshot(GetTransactionSnapshot(false));
  		OldestXmin = InvalidTransactionId;		/* not used */
  	}
  	else
Index: src/backend/commands/cluster.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/commands/cluster.c,v
retrieving revision 1.157
diff -c -c -r1.157 cluster.c
*** src/backend/commands/cluster.c	13 Mar 2007 00:33:39 -0000	1.157
--- src/backend/commands/cluster.c	23 Mar 2007 19:20:45 -0000
***************
*** 204,210 ****
  			/* Start a new transaction for each relation. */
  			StartTransactionCommand();
  			/* functions in indexes may want a snapshot set */
! 			ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  			cluster_rel(rvtc, true);
  			CommitTransactionCommand();
  		}
--- 204,210 ----
  			/* Start a new transaction for each relation. */
  			StartTransactionCommand();
  			/* functions in indexes may want a snapshot set */
! 			ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(true));
  			cluster_rel(rvtc, true);
  			CommitTransactionCommand();
  		}
Index: src/backend/commands/indexcmds.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/commands/indexcmds.c,v
retrieving revision 1.157
diff -c -c -r1.157 indexcmds.c
*** src/backend/commands/indexcmds.c	13 Mar 2007 00:33:39 -0000	1.157
--- src/backend/commands/indexcmds.c	23 Mar 2007 19:20:45 -0000
***************
*** 493,499 ****
  	 * We also set ActiveSnapshot to this snap, since functions in indexes may
  	 * need a snapshot.
  	 */
! 	snapshot = CopySnapshot(GetTransactionSnapshot());
  	ActiveSnapshot = snapshot;
  
  	/*
--- 493,499 ----
  	 * We also set ActiveSnapshot to this snap, since functions in indexes may
  	 * need a snapshot.
  	 */
! 	snapshot = CopySnapshot(GetTransactionSnapshot(false));
  	ActiveSnapshot = snapshot;
  
  	/*
***************
*** 1304,1310 ****
  
  		StartTransactionCommand();
  		/* functions in indexes may want a snapshot set */
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  		if (reindex_relation(relid, true))
  			ereport(NOTICE,
  					(errmsg("table \"%s\" was reindexed",
--- 1304,1310 ----
  
  		StartTransactionCommand();
  		/* functions in indexes may want a snapshot set */
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(true));
  		if (reindex_relation(relid, true))
  			ereport(NOTICE,
  					(errmsg("table \"%s\" was reindexed",
Index: src/backend/commands/trigger.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/commands/trigger.c,v
retrieving revision 1.214
diff -c -c -r1.214 trigger.c
*** src/backend/commands/trigger.c	19 Mar 2007 23:38:29 -0000	1.214
--- src/backend/commands/trigger.c	23 Mar 2007 19:20:46 -0000
***************
*** 2645,2651 ****
  	 */
  	events = &afterTriggers->events;
  	if (events->head != NULL)
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  
  	/*
  	 * Run all the remaining triggers.	Loop until they are all gone, just in
--- 2645,2651 ----
  	 */
  	events = &afterTriggers->events;
  	if (events->head != NULL)
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  
  	/*
  	 * Run all the remaining triggers.	Loop until they are all gone, just in
Index: src/backend/commands/vacuum.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/commands/vacuum.c,v
retrieving revision 1.349
diff -c -c -r1.349 vacuum.c
*** src/backend/commands/vacuum.c	14 Mar 2007 18:48:55 -0000	1.349
--- src/backend/commands/vacuum.c	23 Mar 2007 19:20:47 -0000
***************
*** 412,418 ****
  				{
  					StartTransactionCommand();
  					/* functions in indexes may want a snapshot set */
! 					ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  				}
  				else
  					old_context = MemoryContextSwitchTo(anl_context);
--- 412,418 ----
  				{
  					StartTransactionCommand();
  					/* functions in indexes may want a snapshot set */
! 					ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  				}
  				else
  					old_context = MemoryContextSwitchTo(anl_context);
***************
*** 470,476 ****
  		 * necessary if we are called from autovacuum because autovacuum might
  		 * continue on to do an ANALYZE-only call.
  		 */
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  	}
  
  	if (vacstmt->vacuum && !IsAutoVacuumWorkerProcess())
--- 470,476 ----
  		 * necessary if we are called from autovacuum because autovacuum might
  		 * continue on to do an ANALYZE-only call.
  		 */
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  	}
  
  	if (vacstmt->vacuum && !IsAutoVacuumWorkerProcess())
***************
*** 964,970 ****
  	if (vacstmt->full)
  	{
  		/* functions in indexes may want a snapshot set */
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  	}
  	else
  	{
--- 964,970 ----
  	if (vacstmt->full)
  	{
  		/* functions in indexes may want a snapshot set */
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  	}
  	else
  	{
Index: src/backend/executor/functions.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/executor/functions.c,v
retrieving revision 1.112
diff -c -c -r1.112 functions.c
*** src/backend/executor/functions.c	13 Mar 2007 00:33:40 -0000	1.112
--- src/backend/executor/functions.c	23 Mar 2007 19:20:48 -0000
***************
*** 300,306 ****
  	else
  	{
  		CommandCounterIncrement();
! 		snapshot = CopySnapshot(GetTransactionSnapshot());
  	}
  
  	if (IsA(es->stmt, PlannedStmt))
--- 300,306 ----
  	else
  	{
  		CommandCounterIncrement();
! 		snapshot = CopySnapshot(GetTransactionSnapshot(false));
  	}
  
  	if (IsA(es->stmt, PlannedStmt))
Index: src/backend/executor/spi.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/executor/spi.c,v
retrieving revision 1.173
diff -c -c -r1.173 spi.c
*** src/backend/executor/spi.c	17 Mar 2007 03:15:38 -0000	1.173
--- src/backend/executor/spi.c	23 Mar 2007 19:20:48 -0000
***************
*** 997,1003 ****
  	else
  	{
  		CommandCounterIncrement();
! 		snapshot = GetTransactionSnapshot();
  	}
  
  	/*
--- 997,1003 ----
  	else
  	{
  		CommandCounterIncrement();
! 		snapshot = GetTransactionSnapshot(false);
  	}
  
  	/*
***************
*** 1530,1536 ****
  					if (read_only)
  						ActiveSnapshot = CopySnapshot(saveActiveSnapshot);
  					else
! 						ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  				}
  				else
  				{
--- 1530,1536 ----
  					if (read_only)
  						ActiveSnapshot = CopySnapshot(saveActiveSnapshot);
  					else
! 						ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  				}
  				else
  				{
Index: src/backend/postmaster/autovacuum.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/postmaster/autovacuum.c,v
retrieving revision 1.34
diff -c -c -r1.34 autovacuum.c
*** src/backend/postmaster/autovacuum.c	13 Mar 2007 00:33:41 -0000	1.34
--- src/backend/postmaster/autovacuum.c	23 Mar 2007 19:20:49 -0000
***************
*** 868,874 ****
  	StartTransactionCommand();
  
  	/* functions in indexes may want a snapshot set */
! 	ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  
  	/*
  	 * Clean up any dead statistics collector entries for this DB. We always
--- 868,874 ----
  	StartTransactionCommand();
  
  	/* functions in indexes may want a snapshot set */
! 	ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  
  	/*
  	 * Clean up any dead statistics collector entries for this DB. We always
Index: src/backend/storage/ipc/procarray.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/storage/ipc/procarray.c,v
retrieving revision 1.22
diff -c -c -r1.22 procarray.c
*** src/backend/storage/ipc/procarray.c	23 Mar 2007 03:16:39 -0000	1.22
--- src/backend/storage/ipc/procarray.c	23 Mar 2007 19:20:49 -0000
***************
*** 498,504 ****
   *----------
   */
  Snapshot
! GetSnapshotData(Snapshot snapshot, bool serializable)
  {
  	ProcArrayStruct *arrayP = procArray;
  	TransactionId xmin;
--- 498,504 ----
   *----------
   */
  Snapshot
! GetSnapshotData(Snapshot snapshot, bool set_procArray_xmin)
  {
  	ProcArrayStruct *arrayP = procArray;
  	TransactionId xmin;
***************
*** 510,519 ****
  
  	Assert(snapshot != NULL);
  
! 	/* Serializable snapshot must be computed before any other... */
! 	Assert(serializable ?
! 		   !TransactionIdIsValid(MyProc->xmin) :
! 		   TransactionIdIsValid(MyProc->xmin));
  
  	/*
  	 * Allocating space for maxProcs xids is usually overkill; numProcs would
--- 510,517 ----
  
  	Assert(snapshot != NULL);
  
! 	/* Either we set an xmin, or we already have one.  */
! 	Assert(set_procArray_xmin || TransactionIdIsValid(MyProc->xmin));
  
  	/*
  	 * Allocating space for maxProcs xids is usually overkill; numProcs would
***************
*** 656,664 ****
  		}
  	}
  
! 	if (serializable)
  		MyProc->xmin = TransactionXmin = xmin;
! 
  	LWLockRelease(ProcArrayLock);
  
  	/*
--- 654,668 ----
  		}
  	}
  
! 	if (set_procArray_xmin)
! 	{
! 		if (xmin != MyProc->xmin)
! 			fprintf(stderr, "%x:%x: set new xmin old=%x new=%x\n", MyProcPid, MyProc->xid, MyProc->xmin, xmin);
! 		else
! 			fprintf(stderr, "%x:%x: not set\n", MyProcPid, MyProc->xid);
  		MyProc->xmin = TransactionXmin = xmin;
! 	}
! 	
  	LWLockRelease(ProcArrayLock);
  
  	/*
Index: src/backend/tcop/fastpath.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/tcop/fastpath.c,v
retrieving revision 1.96
diff -c -c -r1.96 fastpath.c
*** src/backend/tcop/fastpath.c	3 Mar 2007 19:32:54 -0000	1.96
--- src/backend/tcop/fastpath.c	23 Mar 2007 19:20:49 -0000
***************
*** 308,314 ****
  	 * Now that we know we are in a valid transaction, set snapshot in case
  	 * needed by function itself or one of the datatype I/O routines.
  	 */
! 	ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  
  	/*
  	 * Begin parsing the buffer contents.
--- 308,314 ----
  	 * Now that we know we are in a valid transaction, set snapshot in case
  	 * needed by function itself or one of the datatype I/O routines.
  	 */
! 	ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  
  	/*
  	 * Begin parsing the buffer contents.
Index: src/backend/tcop/postgres.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/tcop/postgres.c,v
retrieving revision 1.529
diff -c -c -r1.529 postgres.c
*** src/backend/tcop/postgres.c	22 Mar 2007 19:55:04 -0000	1.529
--- src/backend/tcop/postgres.c	23 Mar 2007 19:20:51 -0000
***************
*** 738,744 ****
  		{
  			if (needSnapshot)
  			{
! 				ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  				needSnapshot = false;
  			}
  			stmt = (Node *) pg_plan_query(query, boundParams);
--- 738,744 ----
  		{
  			if (needSnapshot)
  			{
! 				ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(true));
  				needSnapshot = false;
  			}
  			stmt = (Node *) pg_plan_query(query, boundParams);
Index: src/backend/tcop/pquery.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/tcop/pquery.c,v
retrieving revision 1.115
diff -c -c -r1.115 pquery.c
*** src/backend/tcop/pquery.c	13 Mar 2007 00:33:42 -0000	1.115
--- src/backend/tcop/pquery.c	23 Mar 2007 19:20:51 -0000
***************
*** 154,160 ****
  	 * Must always set snapshot for plannable queries.	Note we assume that
  	 * caller will take care of restoring ActiveSnapshot on exit/error.
  	 */
! 	ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  
  	/*
  	 * Create the QueryDesc object
--- 154,160 ----
  	 * Must always set snapshot for plannable queries.	Note we assume that
  	 * caller will take care of restoring ActiveSnapshot on exit/error.
  	 */
! 	ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  
  	/*
  	 * Create the QueryDesc object
***************
*** 489,495 ****
  				if (snapshot)
  					ActiveSnapshot = CopySnapshot(snapshot);
  				else
! 					ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  
  				/*
  				 * Create QueryDesc in portal's context; for the moment, set
--- 489,495 ----
  				if (snapshot)
  					ActiveSnapshot = CopySnapshot(snapshot);
  				else
! 					ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  
  				/*
  				 * Create QueryDesc in portal's context; for the moment, set
***************
*** 1163,1169 ****
  		  IsA(utilityStmt, NotifyStmt) ||
  		  IsA(utilityStmt, UnlistenStmt) ||
  		  IsA(utilityStmt, CheckPointStmt)))
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  	else
  		ActiveSnapshot = NULL;
  
--- 1163,1169 ----
  		  IsA(utilityStmt, NotifyStmt) ||
  		  IsA(utilityStmt, UnlistenStmt) ||
  		  IsA(utilityStmt, CheckPointStmt)))
! 		ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  	else
  		ActiveSnapshot = NULL;
  
Index: src/backend/utils/adt/ri_triggers.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v
retrieving revision 1.92
diff -c -c -r1.92 ri_triggers.c
*** src/backend/utils/adt/ri_triggers.c	15 Mar 2007 23:12:06 -0000	1.92
--- src/backend/utils/adt/ri_triggers.c	23 Mar 2007 19:20:52 -0000
***************
*** 3283,3289 ****
  	{
  		CommandCounterIncrement();		/* be sure all my own work is visible */
  		test_snapshot = CopySnapshot(GetLatestSnapshot());
! 		crosscheck_snapshot = CopySnapshot(GetTransactionSnapshot());
  	}
  	else
  	{
--- 3283,3289 ----
  	{
  		CommandCounterIncrement();		/* be sure all my own work is visible */
  		test_snapshot = CopySnapshot(GetLatestSnapshot());
! 		crosscheck_snapshot = CopySnapshot(GetTransactionSnapshot(false));
  	}
  	else
  	{
Index: src/backend/utils/time/tqual.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/utils/time/tqual.c,v
retrieving revision 1.101
diff -c -c -r1.101 tqual.c
*** src/backend/utils/time/tqual.c	5 Jan 2007 22:19:47 -0000	1.101
--- src/backend/utils/time/tqual.c	23 Mar 2007 19:20:53 -0000
***************
*** 1202,1208 ****
   * the result with CopySnapshot() if it is to be used very long.
   */
  Snapshot
! GetTransactionSnapshot(void)
  {
  	/* First call in transaction? */
  	if (SerializableSnapshot == NULL)
--- 1202,1208 ----
   * the result with CopySnapshot() if it is to be used very long.
   */
  Snapshot
! GetTransactionSnapshot(bool set_procArray_xmin)
  {
  	/* First call in transaction? */
  	if (SerializableSnapshot == NULL)
***************
*** 1214,1220 ****
  	if (IsXactIsoLevelSerializable)
  		return SerializableSnapshot;
  
! 	LatestSnapshot = GetSnapshotData(&LatestSnapshotData, false);
  
  	return LatestSnapshot;
  }
--- 1214,1221 ----
  	if (IsXactIsoLevelSerializable)
  		return SerializableSnapshot;
  
! 	LatestSnapshot = GetSnapshotData(&LatestSnapshotData,
! 	/* we know we are not Serializable */ set_procArray_xmin);
  
  	return LatestSnapshot;
  }
Index: src/include/utils/tqual.h
===================================================================
RCS file: /cvsroot/pgsql/src/include/utils/tqual.h,v
retrieving revision 1.65
diff -c -c -r1.65 tqual.h
*** src/include/utils/tqual.h	5 Jan 2007 22:19:59 -0000	1.65
--- src/include/utils/tqual.h	23 Mar 2007 19:20:54 -0000
***************
*** 142,154 ****
  extern HTSV_Result HeapTupleSatisfiesVacuum(HeapTupleHeader tuple,
  						 TransactionId OldestXmin, Buffer buffer);
  
! extern Snapshot GetTransactionSnapshot(void);
  extern Snapshot GetLatestSnapshot(void);
  extern Snapshot CopySnapshot(Snapshot snapshot);
  extern void FreeSnapshot(Snapshot snapshot);
  extern void FreeXactSnapshot(void);
  
  /* in procarray.c; declared here to avoid including tqual.h in procarray.h: */
! extern Snapshot GetSnapshotData(Snapshot snapshot, bool serializable);
  
  #endif   /* TQUAL_H */
--- 142,154 ----
  extern HTSV_Result HeapTupleSatisfiesVacuum(HeapTupleHeader tuple,
  						 TransactionId OldestXmin, Buffer buffer);
  
! extern Snapshot GetTransactionSnapshot(bool set_procArray_xmin);
  extern Snapshot GetLatestSnapshot(void);
  extern Snapshot CopySnapshot(Snapshot snapshot);
  extern void FreeSnapshot(Snapshot snapshot);
  extern void FreeXactSnapshot(void);
  
  /* in procarray.c; declared here to avoid including tqual.h in procarray.h: */
! extern Snapshot GetSnapshotData(Snapshot snapshot, bool set_procArray_xmin);
  
  #endif   /* TQUAL_H */
Index: src/pl/plpgsql/src/pl_exec.c
===================================================================
RCS file: /cvsroot/pgsql/src/pl/plpgsql/src/pl_exec.c,v
retrieving revision 1.190
diff -c -c -r1.190 pl_exec.c
*** src/pl/plpgsql/src/pl_exec.c	15 Mar 2007 23:12:07 -0000	1.190
--- src/pl/plpgsql/src/pl_exec.c	23 Mar 2007 19:20:55 -0000
***************
*** 4124,4130 ****
  		if (!estate->readonly_func)
  		{
  			CommandCounterIncrement();
! 			ActiveSnapshot = CopySnapshot(GetTransactionSnapshot());
  		}
  
  		/*
--- 4124,4130 ----
  		if (!estate->readonly_func)
  		{
  			CommandCounterIncrement();
! 			ActiveSnapshot = CopySnapshot(GetTransactionSnapshot(false));
  		}
  
  		/*