diff -r 84e2e9c42ef7 contrib/pg_upgrade/Makefile
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/pg_upgrade/Makefile	Fri Dec 12 11:32:03 2008 +0100
@@ -0,0 +1,24 @@
+#-------------------------------------------------------------------------
+#
+# pg_upgrade Makefile
+#
+# $PostgreSQL:  $
+#
+#-------------------------------------------------------------------------
+
+MODULE_big	= pg_upgrade
+OBJS		= pg_upgrade.o rs_heap.o rs_nbtree.o
+DATA_built	= pg_upgrade.sql
+#DATA      	= uninstall_pgstattuple.sql
+
+ifdef USE_PGXS
+PG_CONFIG = pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
+include $(PGXS)
+else
+subdir = contrib/pg_upgrade
+top_builddir = ../..
+include $(top_builddir)/src/Makefile.global
+include $(top_srcdir)/contrib/contrib-global.mk
+endif
+
diff -r 84e2e9c42ef7 contrib/pg_upgrade/pg_upgrade.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/pg_upgrade/pg_upgrade.c	Fri Dec 12 11:32:03 2008 +0100
@@ -0,0 +1,133 @@
+#include "postgres.h"
+
+#include "fmgr.h"
+#include "funcapi.h"
+#include "access/clog.h"
+#include "access/heapam.h"
+#include "access/htup.h"
+#include "catalog/namespace.h"
+#include "storage/bufmgr.h"
+#include "storage/bufpage.h"
+#include "storage/relfilenode.h"
+#include "utils/builtins.h"
+#include "utils/rel.h"
+
+#include "miscadmin.h"
+
+
+PG_MODULE_MAGIC;
+
+
+PG_FUNCTION_INFO_V1(rscheck_rel_by_oid);
+PG_FUNCTION_INFO_V1(rscheck_rel_by_name);
+
+/* 
+ * Return list of visible items, its count and size. We don't need count
+ * dead and deleted tuples.
+ * List is ended with zeroes 
+ */
+HeapTuple
+page_get_visible_items(Page page, BlockNumber block, int *items, Size *size, bool isHeap)
+{
+	OffsetNumber 	i;
+	OffsetNumber 	maxoff;
+	ItemId			iid;
+	HeapTupleHeader tph;
+	HeapTuple		vi_list = NULL;
+	int				count = 0;
+	Size			occupied = 0;
+
+	maxoff = PageGetMaxOffsetNumber(page);
+
+	if(isHeap)
+		vi_list = palloc0(sizeof(HeapTupleData)*(maxoff+1));
+		
+	for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
+	{
+		iid = PageGetItemId(page, i);
+		if(ItemIdIsNormal(iid))
+		{
+			if(isHeap)
+			{
+				XLogRecPtr lsn;
+				tph = (HeapTupleHeader) PageGetItem(page, iid);
+
+				/* we need to count only really visible tuples. Other should be removed during page conversion */
+				if( TRANSACTION_STATUS_COMMITTED != TransactionIdGetStatus(HeapTupleHeaderGetXmin(tph), &lsn) ||
+					TRANSACTION_STATUS_COMMITTED == TransactionIdGetStatus(HeapTupleHeaderGetXmax(tph), &lsn) )
+				continue;
+
+				vi_list[count].t_data = (HeapTupleHeader) PageGetItem(page, iid);
+				vi_list[count].t_len = ItemIdGetLength(iid);
+				ItemPointerSet(&(vi_list[count].t_self), block, i);
+			}	
+			occupied += MAXALIGN(ItemIdGetLength(iid));
+			count++;
+		}
+	}
+
+	if(items != NULL)
+		*items = count;
+	if(size != NULL)
+		*size = occupied;
+
+	return vi_list;
+}
+
+int
+rscheck_rel(Relation rel)
+{
+	uint32		blkcnt;
+	uint32 		modified = 0;          
+
+	blkcnt = RelationGetNumberOfBlocks(rel);
+//	elog(NOTICE,"Start reserved space check - relation %s",rel->rd_rel->relname);
+	elog(NOTICE,"Total blocks for processing: %i", blkcnt);
+
+	switch(rel->rd_rel->relkind)
+	{
+		case 'r' :
+		case 't' : rs_heap(rel);
+				   break;
+		default : elog(ERROR, "Cannot reserve a space. Unsupported relation kind.");
+	}
+	elog(NOTICE,"Total modified blocks: %i", modified);
+
+	return 0;
+}
+
+Datum
+rscheck_rel_by_name(PG_FUNCTION_ARGS)
+{
+	text       *relname = PG_GETARG_TEXT_P(0);
+	RangeVar   *relrv;
+	Relation    rel;
+
+	if (!superuser())
+		ereport(ERROR,
+		(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+		(errmsg("must be superuser to use rs_check functions"))));
+
+	/* open relation */
+	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
+	rel = relation_openrv(relrv, AccessExclusiveLock);
+
+	return rscheck_rel(rel);
+}
+
+Datum
+rscheck_rel_by_oid(PG_FUNCTION_ARGS)
+{
+	Relation    rel;
+
+	if (!superuser())
+		ereport(ERROR,
+		(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+		(errmsg("must be superuser to use rs_check functions"))));
+
+	Oid	relID = PG_GETARG_OID(0);
+	rel = relation_open(relID,  AccessExclusiveLock);
+
+	return rscheck_rel(rel);
+}
+
diff -r 84e2e9c42ef7 contrib/pg_upgrade/pg_upgrade.sql.in
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/pg_upgrade/pg_upgrade.sql.in	Fri Dec 12 11:32:03 2008 +0100
@@ -0,0 +1,8 @@
+CREATE OR REPLACE FUNCTION rs_check(IN relid oid)
+RETURNS int
+AS '$libdir/pg_upgrade','rscheck_rel_by_oid' LANGUAGE C STRICT;
+
+CREATE OR REPLACE FUNCTION rs_check(IN relname text)
+RETURNS int
+AS '$libdir/pg_upgrade','rscheck_rel_by_name' LANGUAGE C STRICT;
+
diff -r 84e2e9c42ef7 contrib/pg_upgrade/rs_check.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/pg_upgrade/rs_check.h	Fri Dec 12 11:32:03 2008 +0100
@@ -0,0 +1,8 @@
+#include "access/htup.h"
+#include "storage/bufpage.h"
+#include "utils/rel.h"
+
+extern HeapTuple page_get_visible_items(Page page, BlockNumber block, int *items, Size *size, bool isHeap);
+extern int rs_heap(Relation rel);
+extern int rs_nbtree(Relation rel);
+
diff -r 84e2e9c42ef7 contrib/pg_upgrade/rs_heap.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/pg_upgrade/rs_heap.c	Fri Dec 12 11:32:03 2008 +0100
@@ -0,0 +1,79 @@
+#include "postgres.h"
+
+#include "access/clog.h"
+#include "access/heapam.h"
+#include "catalog/namespace.h"
+#include "storage/bufmgr.h"
+#include "storage/relfilenode.h"
+#include "rs_check.h"
+
+void
+rs_heap_move_tuple(Relation rel, HeapTuple vi_list, int requested_size)
+{
+	HeapTuple tuple;
+	int n;
+
+	for(n = 0; requested_size > 0 && vi_list[n].t_data != NULL; n++)
+	{
+		tuple = heap_copytuple(&vi_list[n]);
+		simple_heap_update(rel, &tuple->t_self, tuple);
+		pfree(tuple);
+		requested_size -= MAXALIGN(vi_list[n].t_len);
+	}
+}
+
+int
+rs_heap(Relation rel)
+{
+	BlockNumber	blkno;
+	uint32		blkcnt, upgraded = 0;          
+	Buffer		buffer;
+	int			items;
+	Size		space_occupied;
+	Size		space_max;
+	Size		space_reserved;
+
+	blkcnt = RelationGetNumberOfBlocks(rel);
+
+	Assert(rel->rd_rel->relkind == 'r' || rel->rd_rel->relkind == 't');
+
+	for(blkno = 0; blkno < blkcnt; blkno++)
+	{
+		HeapTuple vi;
+
+		if( (blkno+1) % 1000 == 0 )
+			elog(NOTICE,"%i blocks has been processed.", blkno+1);
+
+		buffer = ReadBuffer(rel, blkno);
+		LockBuffer(buffer, BUFFER_LOCK_SHARE);
+
+		vi = page_get_visible_items(BufferGetPage(buffer),
+									blkno,
+									&items, &space_occupied,
+									true); 
+
+		space_max = PageGetMaxDataSpace(BufferGetPage(buffer));
+
+		space_reserved = RelationGetReservedSpacePerPage(rel)+
+						 items*RelationGetReservedSpacePerTuple(rel);
+
+		LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
+
+		if(space_occupied+space_reserved > space_max)
+		{
+			elog(NOTICE,"Block %i needs cleanup. %i+%i>%i", blkno, 
+					space_occupied, space_reserved,space_max );
+
+			upgraded++;
+			rs_heap_move_tuple(rel, vi, space_occupied+space_reserved-space_max);
+		}
+
+		if(vi != NULL) pfree(vi);
+		ReleaseBuffer(buffer);
+	} 
+	relation_close(rel,AccessExclusiveLock);
+	elog(NOTICE,"Total upgraded blocks: %i", upgraded);
+
+	return 0;
+}
+
diff -r 84e2e9c42ef7 contrib/pg_upgrade/rs_nbtree.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/pg_upgrade/rs_nbtree.c	Fri Dec 12 11:32:03 2008 +0100
@@ -0,0 +1,58 @@
+#include "postgres.h"
+
+#include "rs_check.h"
+
+int rs_nbtree(Relation rel)
+{
+	elog(ERROR,"Reservation space is not supported for BTree.");
+	return 0;
+}
+
+/*
+ * _bt_resever_space -- reserve space on page for future in-place upgrade
+ */
+/*
+void
+_bt_reservespace(Relation rel, Buffer buffer)
+{
+	BTPageOpaque lpageop;
+	bool		is_root;
+	bool		is_only;
+	bool		newitemonleft;
+	Buffer		rbuffer;
+	Page		page;
+ 	BTStack     stack;
+
+
+	page = BufferGetPage(buffer);
+	lpageop = (BTPageOpaque) PageGetSpecialPointer(page);
+	is_root = P_ISROOT(lpageop);
+	is_only = P_LEFTMOST(lpageop) && P_RIGHTMOST(lpageop);
+
+*/	/* Choose the split point */
+//	firstright = _bt_findsplitloc(rel, page,
+//								  InvalidOffsetNumber, 0,
+//								  &newitemonleft);
+
+	/* split the buffer into left and right halves */
+	//rbuffer = _bt_split(rel, buffer, firstright,
+		//			 InvalidOffsetNumber, 0, NULL, newitemonleft);
+
+	/*----------
+	 * By here,
+	 *
+	 *		+  our target page has been split;
+	 *		+  the original tuple has been inserted;
+	 *		+  we have write locks on both the old (left half)
+	 *		   and new (right half) buffers, after the split; and
+	 *		+  we know the key we want to insert into the parent
+	 *		   (it's the "high key" on the left child page).
+	 *
+	 * We're ready to do the parent insertion.  We need to hold onto the
+	 * locks for the child pages until we locate the parent, but we can
+	 * release them before doing the actual insertion (see Lehman and Yao
+	 * for the reasoning).
+	 *----------
+	 */
+//	_bt_insert_parent(rel, buffer, rbuffer, stack, is_root, is_only);
+//}