Install infrastructure for shared-memory free space map. Doesn't actually

do anything yet, but it has the necessary connections to initialization
and so forth.  Make some gestures towards allowing number of blocks in
a relation to be BlockNumber, ie, unsigned int, rather than signed int.
(I doubt I got all the places that are sloppy about it, yet.)  On the
way, replace the hardwired NLOCKS_PER_XACT fudge factor with a GUC
variable.

Author: tglsfdc

doc/src/sgml/runtime.sgml

@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.69 2001/06/23 00:03:10 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.70 2001/06/27 23:31:37 tgl Exp $
 -->
 
 <Chapter Id="runtime">
@@ -1131,6 +1131,42 @@ dynamic_library_path = '/usr/local/lib:/home/my_project/lib:$libdir:$libdir/cont
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term>MAX_FSM_RELATIONS (<type>integer</type>)</term>
+      <listitem>
+       <para>
+        Sets the maximum number of relations (tables) for which free space
+	will be tracked in the shared free-space map.
+	The default is 100.  This option can only be set at server start.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term>MAX_FSM_PAGES (<type>integer</type>)</term>
+      <listitem>
+       <para>
+        Sets the maximum number of disk pages for which free space
+	will be tracked in the shared free-space map.
+	The default is 10000.  This option can only be set at server start.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term>MAX_LOCKS_PER_XACT (<type>integer</type>)</term>
+      <listitem>
+       <para>
+        The shared lock table is sized on the assumption that at most
+	max_locks_per_xact * max_connections distinct objects will need
+	to be locked at any one time.  The default, 64, has historically
+	proven sufficient, but you might need to raise this value if you
+	have clients that touch many different tables in a single transaction.
+	This option can only be set at server start.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term>PORT (<type>integer</type>)</term>
       <listitem>

src/backend/access/hash/hashpage.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/hash/hashpage.c,v 1.30 2001/03/07 21:20:26 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/hash/hashpage.c,v 1.31 2001/06/27 23:31:37 tgl Exp $
  *
  * NOTES
  *	  Postgres hash pages look like ordinary relation pages.  The opaque
@@ -70,18 +70,15 @@ _hash_metapinit(Relation rel)
 	int			nbuckets;
 	uint32		nelem;			/* number elements */
 	uint32		lg2nelem;		/* _hash_log2(nelem)   */
-	uint32		nblocks;
 	uint16		i;
 
 	/* can't be sharing this with anyone, now... */
 	if (USELOCKING)
 		LockRelation(rel, AccessExclusiveLock);
 
-	if ((nblocks = RelationGetNumberOfBlocks(rel)) != 0)
-	{
+	if (RelationGetNumberOfBlocks(rel) != 0)
 		elog(ERROR, "Cannot initialize non-empty hash table %s",
 			 RelationGetRelationName(rel));
-	}
 
 	metabuf = _hash_getbuf(rel, HASH_METAPAGE, HASH_WRITE);
 	pg = BufferGetPage(metabuf);

src/backend/access/heap/heapam.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.119 2001/06/22 19:16:20 wieck Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.120 2001/06/27 23:31:38 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -121,8 +121,8 @@ heapgettup(Relation relation,
 {
 	ItemId		lpp;
 	Page		dp;
-	int			page;
-	int			pages;
+	BlockNumber	page;
+	BlockNumber	pages;
 	int			lines;
 	OffsetNumber lineoff;
 	int			linesleft;
@@ -172,7 +172,7 @@ heapgettup(Relation relation,
 	/*
 	 * return null immediately if relation is empty
 	 */
-	if (!(pages = relation->rd_nblocks))
+	if ((pages = relation->rd_nblocks) == 0)
 	{
 		if (BufferIsValid(*buffer))
 			ReleaseBuffer(*buffer);
@@ -233,15 +233,8 @@ heapgettup(Relation relation,
 		{
 			page = ItemPointerGetBlockNumber(tid);		/* current page */
 		}
-		if (page < 0)
-		{
-			if (BufferIsValid(*buffer))
-				ReleaseBuffer(*buffer);
-			*buffer = InvalidBuffer;
-			tuple->t_datamcxt = NULL;
-			tuple->t_data = NULL;
-			return;
-		}
+
+		Assert(page < pages);
 
 		*buffer = ReleaseAndReadBuffer(*buffer,
 									   relation,
@@ -283,15 +276,7 @@ heapgettup(Relation relation,
 				OffsetNumberNext(ItemPointerGetOffsetNumber(tid));
 		}
 
-		if (page >= pages)
-		{
-			if (BufferIsValid(*buffer))
-				ReleaseBuffer(*buffer);
-			*buffer = InvalidBuffer;
-			tuple->t_datamcxt = NULL;
-			tuple->t_data = NULL;
-			return;
-		}
+		Assert(page < pages);
 
 		*buffer = ReleaseAndReadBuffer(*buffer,
 									   relation,
@@ -369,12 +354,11 @@ heapgettup(Relation relation,
 		 * and it's time to move to the next.
 		 */
 		LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
-		page = (dir < 0) ? (page - 1) : (page + 1);
 
 		/*
 		 * return NULL if we've exhausted all the pages
 		 */
-		if (page < 0 || page >= pages)
+		if ((dir < 0) ? (page == 0) : (page+1 >= pages))
 		{
 			if (BufferIsValid(*buffer))
 				ReleaseBuffer(*buffer);
@@ -384,6 +368,10 @@ heapgettup(Relation relation,
 			return;
 		}
 
+		page = (dir < 0) ? (page - 1) : (page + 1);
+
+		Assert(page < pages);
+
 		*buffer = ReleaseAndReadBuffer(*buffer,
 									   relation,
 									   page,

src/backend/access/heap/hio.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Id: hio.c,v 1.39 2001/05/16 22:35:12 tgl Exp $
+ *	  $Id: hio.c,v 1.40 2001/06/27 23:31:38 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -147,7 +147,7 @@ RelationGetBufferForTuple(Relation relation, Size len,
 	 */
 	relation->rd_nblocks = RelationGetNumberOfBlocks(relation);
 
-	if ((BlockNumber) relation->rd_nblocks > oldnblocks)
+	if (relation->rd_nblocks > oldnblocks)
 	{
 		/*
 		 * Someone else has indeed extended the relation recently.

src/backend/access/nbtree/nbtpage.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtpage.c,v 1.51 2001/03/22 03:59:14 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtpage.c,v 1.52 2001/06/27 23:31:38 tgl Exp $
  *
  *	NOTES
  *	   Postgres btree pages look like ordinary relation pages.	The opaque
@@ -55,19 +55,16 @@ _bt_metapinit(Relation rel)
 {
 	Buffer		buf;
 	Page		pg;
-	int			nblocks;
 	BTMetaPageData metad;
 	BTPageOpaque op;
 
 	/* can't be sharing this with anyone, now... */
 	if (USELOCKING)
 		LockRelation(rel, AccessExclusiveLock);
 
-	if ((nblocks = RelationGetNumberOfBlocks(rel)) != 0)
-	{
+	if (RelationGetNumberOfBlocks(rel) != 0)
 		elog(ERROR, "Cannot initialize non-empty btree %s",
 			 RelationGetRelationName(rel));
-	}
 
 	buf = ReadBuffer(rel, P_NEW);
 	pg = BufferGetPage(buf);

src/backend/catalog/heap.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.168 2001/06/18 16:13:21 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.169 2001/06/27 23:31:38 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1089,6 +1089,7 @@ RelationTruncateIndexes(Oid heapId)
 		/* Now truncate the actual data and set blocks to zero */
 		smgrtruncate(DEFAULT_SMGR, currentIndex, 0);
 		currentIndex->rd_nblocks = 0;
+		currentIndex->rd_targblock = InvalidBlockNumber;
 
 		/* Initialize the index and rebuild */
 		InitIndexStrategy(indexInfo->ii_NumIndexAttrs,
@@ -1143,9 +1144,9 @@ heap_truncate(char *relname)
 	DropRelationBuffers(rel);
 
 	/* Now truncate the actual data and set blocks to zero */
-
 	smgrtruncate(DEFAULT_SMGR, rel, 0);
 	rel->rd_nblocks = 0;
+	rel->rd_targblock = InvalidBlockNumber;
 
 	/* If this relation has indexes, truncate the indexes too */
 	RelationTruncateIndexes(rid);

src/backend/catalog/index.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.154 2001/06/12 05:55:49 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.155 2001/06/27 23:31:38 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1456,7 +1456,7 @@ UpdateStats(Oid relid, double reltuples)
 	Relation	pg_class;
 	HeapTuple	tuple;
 	HeapTuple	newtup;
-	long		relpages;
+	BlockNumber	relpages;
 	int			i;
 	Form_pg_class rd_rel;
 	Relation	idescs[Num_pg_class_indices];
@@ -1558,15 +1558,15 @@ UpdateStats(Oid relid, double reltuples)
 			reltuples = 1000;
 		}
 		else
-			reltuples = relpages * NTUPLES_PER_PAGE(whichRel->rd_rel->relnatts);
+			reltuples = (double) relpages * NTUPLES_PER_PAGE(whichRel->rd_rel->relnatts);
 	}
 
 	/*
 	 * We shouldn't have to do this, but we do...  Modify the reldesc in
 	 * place with the new values so that the cache contains the latest
 	 * copy.
 	 */
-	whichRel->rd_rel->relpages = relpages;
+	whichRel->rd_rel->relpages = (int32) relpages;
 	whichRel->rd_rel->reltuples = reltuples;
 
 	/*
@@ -1581,7 +1581,7 @@ UpdateStats(Oid relid, double reltuples)
 		 */
 		rd_rel = (Form_pg_class) GETSTRUCT(tuple);
 		LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_EXCLUSIVE);
-		rd_rel->relpages = relpages;
+		rd_rel->relpages = (int32) relpages;
 		rd_rel->reltuples = reltuples;
 		LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
 		WriteNoReleaseBuffer(pg_class_scan->rs_cbuf);
@@ -1600,7 +1600,7 @@ UpdateStats(Oid relid, double reltuples)
 		}
 
 		replace[Anum_pg_class_relpages - 1] = 'r';
-		values[Anum_pg_class_relpages - 1] = Int32GetDatum(relpages);
+		values[Anum_pg_class_relpages - 1] = Int32GetDatum((int32) relpages);
 		replace[Anum_pg_class_reltuples - 1] = 'r';
 		values[Anum_pg_class_reltuples - 1] = Float4GetDatum((float4) reltuples);
 		newtup = heap_modifytuple(tuple, pg_class, values, nulls, replace);
@@ -1962,6 +1962,7 @@ reindex_index(Oid indexId, bool force, bool inplace)
 		/* Now truncate the actual data and set blocks to zero */
 		smgrtruncate(DEFAULT_SMGR, iRel, 0);
 		iRel->rd_nblocks = 0;
+		iRel->rd_targblock = InvalidBlockNumber;
 	}
 
 	/* Initialize the index and rebuild */