Include the backend ID in the relpath of temporary relations.

This allows us to reliably remove all leftover temporary relation files on cluster startup without reference to system catalogs or WAL; therefore, we no longer include temporary relations in XLOG_XACT_COMMIT and XLOG_XACT_ABORT WAL records. Since these changes require including a backend ID in each SharedInvalSmgrMsg, the size of the SharedInvalidationMessage.id field has been reduced from two bytes to one, and the maximum number of connections has been reduced from INT_MAX / 4 to 2^23-1. It would be possible to remove these restrictions by increasing the size of SharedInvalidationMessage by 4 bytes, but right now that doesn't seem like a good trade-off. Review by Jaime Casanova and Tom Lane.
2010-08-13 20:10:54 +00:00 · 2010-08-13 20:10:54 +00:00 · debcec7dc3
parent 3f9479ef3f
commit debcec7dc3
37 changed files with 669 additions and 343 deletions
--- a/doc/src/sgml/storage.sgml
+++ b/doc/src/sgml/storage.sgml
@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.32 2010/02/16 22:34:43 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.33 2010/08/13 20:10:50 rhaas Exp $ -->

 <chapter id="storage">

@ -133,16 +133,20 @@ there.
 </para>

 <para>
-Each table and index is stored in a separate file, named after the table
-or index's <firstterm>filenode</> number, which can be found in
-<structname>pg_class</>.<structfield>relfilenode</>. In addition to the
-main file (a/k/a main fork), each table and index has a <firstterm>free space
-map</> (see <xref linkend="storage-fsm">), which stores information about free
-space available in the relation.  The free space map is stored in a file named
-with the filenode number plus the suffix <literal>_fsm</>.  Tables also have a
-<firstterm>visibility map</>, stored in a fork with the suffix
-<literal>_vm</>, to track which pages are known to have no dead tuples.
-The visibility map is described further in <xref linkend="storage-vm">.
+Each table and index is stored in a separate file.  For ordinary relations,
+these files are named after the table or index's <firstterm>filenode</> number,
+which can be found in <structname>pg_class</>.<structfield>relfilenode</>. But
+for temporary relations, the file name is of the form
+<literal>t<replaceable>BBB</>_<replaceable>FFF</></>, where <replaceable>BBB</>
+is the backend ID of the backend which created the file, and <replaceable>FFF</>
+is the filenode number.  In either case, in addition to the main file (a/k/a
+main fork), each table and index has a <firstterm>free space map</> (see <xref
+linkend="storage-fsm">), which stores information about free space available in
+the relation.  The free space map is stored in a file named with the filenode
+number plus the suffix <literal>_fsm</>.  Tables also have a
+<firstterm>visibility map</>, stored in a fork with the suffix <literal>_vm</>,
+to track which pages are known to have no dead tuples.  The visibility map is
+described further in <xref linkend="storage-vm">.
 </para>

 <caution>
--- a/src/backend/access/heap/visibilitymap.c
+++ b/src/backend/access/heap/visibilitymap.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/visibilitymap.c,v 1.10 2010/04/23 23:21:44 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/visibilitymap.c,v 1.11 2010/08/13 20:10:50 rhaas Exp $
 *
 * INTERFACE ROUTINES
 *		visibilitymap_clear - clear a bit in the visibility map
@ -373,8 +373,7 @@ visibilitymap_truncate(Relation rel, BlockNumber nheapblocks)
 	}

 	/* Truncate the unused VM pages, and send smgr inval message */
-	smgrtruncate(rel->rd_smgr, VISIBILITYMAP_FORKNUM, newnblocks,
-				 rel->rd_istemp);
+	smgrtruncate(rel->rd_smgr, VISIBILITYMAP_FORKNUM, newnblocks);

 	/*
 	 * We might as well update the local smgr_vm_nblocks setting. smgrtruncate
--- a/src/backend/access/nbtree/nbtsort.c
+++ b/src/backend/access/nbtree/nbtsort.c
@ -59,7 +59,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsort.c,v 1.125 2010/04/28 16:10:40 heikki Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsort.c,v 1.126 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -295,9 +295,8 @@ _bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno)
 	}

 	/*
-	 * Now write the page.	We say isTemp = true even if it's not a temp
-	 * index, because there's no need for smgr to schedule an fsync for this
-	 * write; we'll do it ourselves before ending the build.
+	 * Now write the page.	There's no need for smgr to schedule an fsync for
+	 * this write; we'll do it ourselves before ending the build.
 	 */
 	if (blkno == wstate->btws_pages_written)
 	{
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *		$PostgreSQL: pgsql/src/backend/access/transam/twophase.c,v 1.62 2010/07/06 19:18:55 momjian Exp $
+ *		$PostgreSQL: pgsql/src/backend/access/transam/twophase.c,v 1.63 2010/08/13 20:10:50 rhaas Exp $
 *
 * NOTES
 *		Each global transaction is associated with a global transaction
@ -865,8 +865,8 @@ StartPrepare(GlobalTransaction gxact)
 	hdr.prepared_at = gxact->prepared_at;
 	hdr.owner = gxact->owner;
 	hdr.nsubxacts = xactGetCommittedChildren(&children);
-	hdr.ncommitrels = smgrGetPendingDeletes(true, &commitrels, NULL);
-	hdr.nabortrels = smgrGetPendingDeletes(false, &abortrels, NULL);
+	hdr.ncommitrels = smgrGetPendingDeletes(true, &commitrels);
+	hdr.nabortrels = smgrGetPendingDeletes(false, &abortrels);
 	hdr.ninvalmsgs = xactGetCommittedInvalidationMessages(&invalmsgs,
 														  &hdr.initfileinval);
 	StrNCpy(hdr.gid, gxact->gid, GIDSIZE);
@ -1320,13 +1320,13 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 	}
 	for (i = 0; i < ndelrels; i++)
 	{
-		SMgrRelation srel = smgropen(delrels[i]);
+		SMgrRelation srel = smgropen(delrels[i], InvalidBackendId);
 		ForkNumber	fork;

 		for (fork = 0; fork <= MAX_FORKNUM; fork++)
 		{
 			if (smgrexists(srel, fork))
-				smgrdounlink(srel, fork, false, false);
+				smgrdounlink(srel, fork, false);
 		}
 		smgrclose(srel);
 	}
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@ -10,7 +10,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.297 2010/08/13 15:42:21 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.298 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -912,7 +912,6 @@ RecordTransactionCommit(void)
 	TransactionId latestXid = InvalidTransactionId;
 	int			nrels;
 	RelFileNode *rels;
-	bool		haveNonTemp;
 	int			nchildren;
 	TransactionId *children;
 	int			nmsgs = 0;
@ -920,7 +919,7 @@ RecordTransactionCommit(void)
 	bool		RelcacheInitFileInval = false;

 	/* Get data needed for commit record */
-	nrels = smgrGetPendingDeletes(true, &rels, &haveNonTemp);
+	nrels = smgrGetPendingDeletes(true, &rels);
 	nchildren = xactGetCommittedChildren(&children);
 	if (XLogStandbyInfoActive())
 		nmsgs = xactGetCommittedInvalidationMessages(&invalMessages,
@ -1048,7 +1047,7 @@ RecordTransactionCommit(void)
 	 * asynchronous commit if all to-be-deleted tables are temporary though,
 	 * since they are lost anyway if we crash.)
 	 */
-	if (XactSyncCommit || forceSyncCommit || haveNonTemp)
+	if (XactSyncCommit || forceSyncCommit || nrels > 0)
 	{
 		/*
 		 * Synchronous commit case:
@ -1334,7 +1333,7 @@ RecordTransactionAbort(bool isSubXact)
 			 xid);

 	/* Fetch the data we need for the abort record */
-	nrels = smgrGetPendingDeletes(false, &rels, NULL);
+	nrels = smgrGetPendingDeletes(false, &rels);
 	nchildren = xactGetCommittedChildren(&children);

 	/* XXX do we really need a critical section here? */
@ -4474,7 +4473,7 @@ xact_redo_commit(xl_xact_commit *xlrec, TransactionId xid, XLogRecPtr lsn)
 	/* Make sure files supposed to be dropped are dropped */
 	for (i = 0; i < xlrec->nrels; i++)
 	{
-		SMgrRelation srel = smgropen(xlrec->xnodes[i]);
+		SMgrRelation srel = smgropen(xlrec->xnodes[i], InvalidBackendId);
 		ForkNumber	fork;

 		for (fork = 0; fork <= MAX_FORKNUM; fork++)
@ -4482,7 +4481,7 @@ xact_redo_commit(xl_xact_commit *xlrec, TransactionId xid, XLogRecPtr lsn)
 			if (smgrexists(srel, fork))
 			{
 				XLogDropRelation(xlrec->xnodes[i], fork);
-				smgrdounlink(srel, fork, false, true);
+				smgrdounlink(srel, fork, true);
 			}
 		}
 		smgrclose(srel);
@ -4579,7 +4578,7 @@ xact_redo_abort(xl_xact_abort *xlrec, TransactionId xid)
 	/* Make sure files supposed to be dropped are dropped */
 	for (i = 0; i < xlrec->nrels; i++)
 	{
-		SMgrRelation srel = smgropen(xlrec->xnodes[i]);
+		SMgrRelation srel = smgropen(xlrec->xnodes[i], InvalidBackendId);
 		ForkNumber	fork;

 		for (fork = 0; fork <= MAX_FORKNUM; fork++)
@ -4587,7 +4586,7 @@ xact_redo_abort(xl_xact_abort *xlrec, TransactionId xid)
 			if (smgrexists(srel, fork))
 			{
 				XLogDropRelation(xlrec->xnodes[i], fork);
-				smgrdounlink(srel, fork, false, true);
+				smgrdounlink(srel, fork, true);
 			}
 		}
 		smgrclose(srel);
@ -4661,7 +4660,7 @@ xact_desc_commit(StringInfo buf, xl_xact_commit *xlrec)
 		appendStringInfo(buf, "; rels:");
 		for (i = 0; i < xlrec->nrels; i++)
 		{
-			char	   *path = relpath(xlrec->xnodes[i], MAIN_FORKNUM);
+			char	   *path = relpathperm(xlrec->xnodes[i], MAIN_FORKNUM);

 			appendStringInfo(buf, " %s", path);
 			pfree(path);
@ -4716,7 +4715,7 @@ xact_desc_abort(StringInfo buf, xl_xact_abort *xlrec)
 		appendStringInfo(buf, "; rels:");
 		for (i = 0; i < xlrec->nrels; i++)
 		{
-			char	   *path = relpath(xlrec->xnodes[i], MAIN_FORKNUM);
+			char	   *path = relpathperm(xlrec->xnodes[i], MAIN_FORKNUM);

 			appendStringInfo(buf, " %s", path);
 			pfree(path);
--- a/src/backend/access/transam/xlogutils.c
+++ b/src/backend/access/transam/xlogutils.c
@ -11,7 +11,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlogutils.c,v 1.71 2010/07/08 16:08:30 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlogutils.c,v 1.72 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -68,7 +68,7 @@ log_invalid_page(RelFileNode node, ForkNumber forkno, BlockNumber blkno,
 	 */
 	if (log_min_messages <= DEBUG1 || client_min_messages <= DEBUG1)
 	{
-		char	   *path = relpath(node, forkno);
+		char	   *path = relpathperm(node, forkno);

 		if (present)
 			elog(DEBUG1, "page %u of relation %s is uninitialized",
@ -133,7 +133,7 @@ forget_invalid_pages(RelFileNode node, ForkNumber forkno, BlockNumber minblkno)
 		{
 			if (log_min_messages <= DEBUG2 || client_min_messages <= DEBUG2)
 			{
-				char	   *path = relpath(hentry->key.node, forkno);
+				char	   *path = relpathperm(hentry->key.node, forkno);

 				elog(DEBUG2, "page %u of relation %s has been dropped",
 					 hentry->key.blkno, path);
@ -166,7 +166,7 @@ forget_invalid_pages_db(Oid dbid)
 		{
 			if (log_min_messages <= DEBUG2 || client_min_messages <= DEBUG2)
 			{
-				char	   *path = relpath(hentry->key.node, hentry->key.forkno);
+				char	   *path = relpathperm(hentry->key.node, hentry->key.forkno);

 				elog(DEBUG2, "page %u of relation %s has been dropped",
 					 hentry->key.blkno, path);
@ -200,7 +200,7 @@ XLogCheckInvalidPages(void)
 	 */
 	while ((hentry = (xl_invalid_page *) hash_seq_search(&status)) != NULL)
 	{
-		char	   *path = relpath(hentry->key.node, hentry->key.forkno);
+		char	   *path = relpathperm(hentry->key.node, hentry->key.forkno);

 		if (hentry->present)
 			elog(WARNING, "page %u of relation %s was uninitialized",
@ -276,7 +276,7 @@ XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum,
 	Assert(blkno != P_NEW);

 	/* Open the relation at smgr level */
-	smgr = smgropen(rnode);
+	smgr = smgropen(rnode, InvalidBackendId);

 	/*
 	 * Create the target file if it doesn't already exist.  This lets us cope
@ -293,7 +293,7 @@ XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum,
 	if (blkno < lastblock)
 	{
 		/* page exists in file */
-		buffer = ReadBufferWithoutRelcache(rnode, false, forknum, blkno,
+		buffer = ReadBufferWithoutRelcache(rnode, forknum, blkno,
 										   mode, NULL);
 	}
 	else
@ -312,7 +312,7 @@ XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum,
 		{
 			if (buffer != InvalidBuffer)
 				ReleaseBuffer(buffer);
-			buffer = ReadBufferWithoutRelcache(rnode, false, forknum,
+			buffer = ReadBufferWithoutRelcache(rnode, forknum,
 											   P_NEW, mode, NULL);
 			lastblock++;
 		}
--- a/src/backend/catalog/catalog.c
+++ b/src/backend/catalog/catalog.c
@ -10,7 +10,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/catalog.c,v 1.90 2010/04/20 23:48:47 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/catalog.c,v 1.91 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -78,12 +78,37 @@ forkname_to_number(char *forkName)
 }

 /*
- * relpath			- construct path to a relation's file
+ * forkname_chars
+ * 		We use this to figure out whether a filename could be a relation
+ * 		fork (as opposed to an oddly named stray file that somehow ended
+ * 		up in the database directory).  If the passed string begins with
+ * 		a fork name (other than the main fork name), we return its length.
+ * 		If not, we return 0.
+ *
+ * Note that the present coding assumes that there are no fork names which
+ * are prefixes of other fork names.
+ */
+int
+forkname_chars(const char *str)
+{
+	ForkNumber	forkNum;
+
+	for (forkNum = 1; forkNum <= MAX_FORKNUM; forkNum++)
+	{
+		int len = strlen(forkNames[forkNum]);
+		if (strncmp(forkNames[forkNum], str, len) == 0)
+			return len;
+	}
+	return 0;
+}
+
+/*
+ * relpathbackend - construct path to a relation's file
 *
 * Result is a palloc'd string.
 */
 char *
-relpath(RelFileNode rnode, ForkNumber forknum)
+relpathbackend(RelFileNode rnode, BackendId backend, ForkNumber forknum)
 {
 	int			pathlen;
 	char	   *path;
@ -92,6 +117,7 @@ relpath(RelFileNode rnode, ForkNumber forknum)
 	{
 		/* Shared system relations live in {datadir}/global */
 		Assert(rnode.dbNode == 0);
+		Assert(backend == InvalidBackendId);
 		pathlen = 7 + OIDCHARS + 1 + FORKNAMECHARS + 1;
 		path = (char *) palloc(pathlen);
 		if (forknum != MAIN_FORKNUM)
@ -103,29 +129,69 @@ relpath(RelFileNode rnode, ForkNumber forknum)
 	else if (rnode.spcNode == DEFAULTTABLESPACE_OID)
 	{
 		/* The default tablespace is {datadir}/base */
-		pathlen = 5 + OIDCHARS + 1 + OIDCHARS + 1 + FORKNAMECHARS + 1;
-		path = (char *) palloc(pathlen);
-		if (forknum != MAIN_FORKNUM)
-			snprintf(path, pathlen, "base/%u/%u_%s",
-					 rnode.dbNode, rnode.relNode, forkNames[forknum]);
+		if (backend == InvalidBackendId)
+		{
+			pathlen = 5 + OIDCHARS + 1 + OIDCHARS + 1 + FORKNAMECHARS + 1;
+			path = (char *) palloc(pathlen);
+			if (forknum != MAIN_FORKNUM)
+				snprintf(path, pathlen, "base/%u/%u_%s",
+						 rnode.dbNode, rnode.relNode,
+						 forkNames[forknum]);
+			else
+				snprintf(path, pathlen, "base/%u/%u",
+						 rnode.dbNode, rnode.relNode);
+		}
 		else
-			snprintf(path, pathlen, "base/%u/%u",
-					 rnode.dbNode, rnode.relNode);
+		{
+			/* OIDCHARS will suffice for an integer, too */
+			pathlen = 5 + OIDCHARS + 2 + OIDCHARS + 1 + OIDCHARS + 1
+					+ FORKNAMECHARS + 1;
+			path = (char *) palloc(pathlen);
+			if (forknum != MAIN_FORKNUM)
+				snprintf(path, pathlen, "base/%u/t%d_%u_%s",
+						 rnode.dbNode, backend, rnode.relNode,
+						 forkNames[forknum]);
+			else
+				snprintf(path, pathlen, "base/%u/t%d_%u",
+						 rnode.dbNode, backend, rnode.relNode);
+		}
 	}
 	else
 	{
 		/* All other tablespaces are accessed via symlinks */
-		pathlen = 9 + 1 + OIDCHARS + 1 + strlen(TABLESPACE_VERSION_DIRECTORY) +
-			1 + OIDCHARS + 1 + OIDCHARS + 1 + FORKNAMECHARS + 1;
-		path = (char *) palloc(pathlen);
-		if (forknum != MAIN_FORKNUM)
-			snprintf(path, pathlen, "pg_tblspc/%u/%s/%u/%u_%s",
-					 rnode.spcNode, TABLESPACE_VERSION_DIRECTORY,
-					 rnode.dbNode, rnode.relNode, forkNames[forknum]);
+		if (backend == InvalidBackendId)
+		{
+			pathlen = 9 + 1 + OIDCHARS + 1
+					+ strlen(TABLESPACE_VERSION_DIRECTORY) + 1 + OIDCHARS + 1
+					+ OIDCHARS + 1 + FORKNAMECHARS + 1;
+			path = (char *) palloc(pathlen);
+			if (forknum != MAIN_FORKNUM)
+				snprintf(path, pathlen, "pg_tblspc/%u/%s/%u/%u_%s",
+						 rnode.spcNode, TABLESPACE_VERSION_DIRECTORY,
+						 rnode.dbNode, rnode.relNode,
+						 forkNames[forknum]);
+			else
+				snprintf(path, pathlen, "pg_tblspc/%u/%s/%u/%u",
+						 rnode.spcNode, TABLESPACE_VERSION_DIRECTORY,
+						 rnode.dbNode, rnode.relNode);
+		}
 		else
-			snprintf(path, pathlen, "pg_tblspc/%u/%s/%u/%u",
-					 rnode.spcNode, TABLESPACE_VERSION_DIRECTORY,
-					 rnode.dbNode, rnode.relNode);
+		{
+			/* OIDCHARS will suffice for an integer, too */
+			pathlen = 9 + 1 + OIDCHARS + 1
+					+ strlen(TABLESPACE_VERSION_DIRECTORY) + 1 + OIDCHARS + 2
+					+ OIDCHARS + 1 + OIDCHARS + 1 + FORKNAMECHARS + 1;
+			path = (char *) palloc(pathlen);
+			if (forknum != MAIN_FORKNUM)
+				snprintf(path, pathlen, "pg_tblspc/%u/%s/%u/t%d_%u_%s",
+						 rnode.spcNode, TABLESPACE_VERSION_DIRECTORY,
+						 rnode.dbNode, backend, rnode.relNode,
+						 forkNames[forknum]);
+			else
+				snprintf(path, pathlen, "pg_tblspc/%u/%s/%u/t%d_%u",
+						 rnode.spcNode, TABLESPACE_VERSION_DIRECTORY,
+						 rnode.dbNode, backend, rnode.relNode);
+		}
 	}
 	return path;
 }
@ -458,16 +524,23 @@ GetNewOidWithIndex(Relation relation, Oid indexId, AttrNumber oidcolumn)
 * created by bootstrap have preassigned OIDs, so there's no need.
 */
 Oid
-GetNewRelFileNode(Oid reltablespace, Relation pg_class)
+GetNewRelFileNode(Oid reltablespace, Relation pg_class, BackendId backend)
 {
-	RelFileNode rnode;
+	RelFileNodeBackend rnode;
 	char	   *rpath;
 	int			fd;
 	bool		collides;

 	/* This logic should match RelationInitPhysicalAddr */
-	rnode.spcNode = reltablespace ? reltablespace : MyDatabaseTableSpace;
-	rnode.dbNode = (rnode.spcNode == GLOBALTABLESPACE_OID) ? InvalidOid : MyDatabaseId;
+	rnode.node.spcNode = reltablespace ? reltablespace : MyDatabaseTableSpace;
+	rnode.node.dbNode = (rnode.node.spcNode == GLOBALTABLESPACE_OID) ? InvalidOid : MyDatabaseId;
+
+	/*
+	 * The relpath will vary based on the backend ID, so we must initialize
+	 * that properly here to make sure that any collisions based on filename
+	 * are properly detected.
+	 */
+	rnode.backend = backend;

 	do
 	{
@ -475,9 +548,9 @@ GetNewRelFileNode(Oid reltablespace, Relation pg_class)

 		/* Generate the OID */
 		if (pg_class)
-			rnode.relNode = GetNewOid(pg_class);
+			rnode.node.relNode = GetNewOid(pg_class);
 		else
-			rnode.relNode = GetNewObjectId();
+			rnode.node.relNode = GetNewObjectId();

 		/* Check for existing file of same name */
 		rpath = relpath(rnode, MAIN_FORKNUM);
@ -508,5 +581,5 @@ GetNewRelFileNode(Oid reltablespace, Relation pg_class)
 		pfree(rpath);
 	} while (collides);

-	return rnode.relNode;
+	return rnode.node.relNode;
 }
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/heap.c,v 1.374 2010/07/25 23:21:21 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/heap.c,v 1.375 2010/08/13 20:10:50 rhaas Exp $
 *
 *
 * INTERFACE ROUTINES
@ -39,6 +39,7 @@
 #include "catalog/heap.h"
 #include "catalog/index.h"
 #include "catalog/indexing.h"
+#include "catalog/namespace.h"
 #include "catalog/pg_attrdef.h"
 #include "catalog/pg_constraint.h"
 #include "catalog/pg_inherits.h"
@ -994,7 +995,9 @@ heap_create_with_catalog(const char *relname,
 			binary_upgrade_next_toast_relfilenode = InvalidOid;
 		}
 		else
-			relid = GetNewRelFileNode(reltablespace, pg_class_desc);
+			relid = GetNewRelFileNode(reltablespace, pg_class_desc,
+									  isTempOrToastNamespace(relnamespace) ?
+										  MyBackendId : InvalidBackendId);
 	}

 	/*
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/index.c,v 1.337 2010/02/26 02:00:36 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/index.c,v 1.338 2010/08/13 20:10:50 rhaas Exp $
 *
 *
 * INTERFACE ROUTINES
@ -645,7 +645,12 @@ index_create(Oid heapRelationId,
 			binary_upgrade_next_index_relfilenode = InvalidOid;
 		}
 		else
-			indexRelationId = GetNewRelFileNode(tableSpaceId, pg_class);
+		{
+			indexRelationId =
+				GetNewRelFileNode(tableSpaceId, pg_class,
+								  heapRelation->rd_istemp ?
+									MyBackendId : InvalidBackendId);
+		}
 	}

 	/*
--- a/src/backend/catalog/namespace.c
+++ b/src/backend/catalog/namespace.c
@ -13,7 +13,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/namespace.c,v 1.128 2010/08/13 16:27:11 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/namespace.c,v 1.129 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -2588,7 +2588,7 @@ isOtherTempNamespace(Oid namespaceId)
 * GetTempNamespaceBackendId - if the given namespace is a temporary-table
 * namespace (either my own, or another backend's), return the BackendId
 * that owns it.  Temporary-toast-table namespaces are included, too.
- * If it isn't a temp namespace, return -1.
+ * If it isn't a temp namespace, return InvalidBackendId.
 */
 int
 GetTempNamespaceBackendId(Oid namespaceId)
@ -2599,13 +2599,13 @@ GetTempNamespaceBackendId(Oid namespaceId)
 	/* See if the namespace name starts with "pg_temp_" or "pg_toast_temp_" */
 	nspname = get_namespace_name(namespaceId);
 	if (!nspname)
-		return -1;				/* no such namespace? */
+		return InvalidBackendId;				/* no such namespace? */
 	if (strncmp(nspname, "pg_temp_", 8) == 0)
 		result = atoi(nspname + 8);
 	else if (strncmp(nspname, "pg_toast_temp_", 14) == 0)
 		result = atoi(nspname + 14);
 	else
-		result = -1;
+		result = InvalidBackendId;
 	pfree(nspname);
 	return result;
 }
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/storage.c,v 1.10 2010/02/09 21:43:30 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/storage.c,v 1.11 2010/08/13 20:10:50 rhaas Exp $
 *
 * NOTES
 *	  Some of this code used to be in storage/smgr/smgr.c, and the
@ -52,7 +52,7 @@
 typedef struct PendingRelDelete
 {
 	RelFileNode relnode;		/* relation that may need to be deleted */
-	bool		isTemp;			/* is it a temporary relation? */
+	BackendId	backend;		/* InvalidBackendId if not a temp rel */
 	bool		atCommit;		/* T=delete at commit; F=delete at abort */
 	int			nestLevel;		/* xact nesting level of request */
 	struct PendingRelDelete *next;		/* linked-list link */
@ -102,8 +102,9 @@ RelationCreateStorage(RelFileNode rnode, bool istemp)
 	XLogRecData rdata;
 	xl_smgr_create xlrec;
 	SMgrRelation srel;
+	BackendId	backend = istemp ? MyBackendId : InvalidBackendId;

-	srel = smgropen(rnode);
+	srel = smgropen(rnode, backend);
 	smgrcreate(srel, MAIN_FORKNUM, false);

 	if (!istemp)
@ -125,7 +126,7 @@ RelationCreateStorage(RelFileNode rnode, bool istemp)
 	pending = (PendingRelDelete *)
 		MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
 	pending->relnode = rnode;
-	pending->isTemp = istemp;
+	pending->backend = backend;
 	pending->atCommit = false;	/* delete if abort */
 	pending->nestLevel = GetCurrentTransactionNestLevel();
 	pending->next = pendingDeletes;
@ -145,7 +146,7 @@ RelationDropStorage(Relation rel)
 	pending = (PendingRelDelete *)
 		MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
 	pending->relnode = rel->rd_node;
-	pending->isTemp = rel->rd_istemp;
+	pending->backend = rel->rd_backend;
 	pending->atCommit = true;	/* delete if commit */
 	pending->nestLevel = GetCurrentTransactionNestLevel();
 	pending->next = pendingDeletes;
@ -283,7 +284,7 @@ RelationTruncate(Relation rel, BlockNumber nblocks)
 	}

 	/* Do the real work */
-	smgrtruncate(rel->rd_smgr, MAIN_FORKNUM, nblocks, rel->rd_istemp);
+	smgrtruncate(rel->rd_smgr, MAIN_FORKNUM, nblocks);
 }

 /*
@ -291,6 +292,11 @@ RelationTruncate(Relation rel, BlockNumber nblocks)
 *
 * This also runs when aborting a subxact; we want to clean up a failed
 * subxact immediately.
+ *
+ * Note: It's possible that we're being asked to remove a relation that has
+ * no physical storage in any fork. In particular, it's possible that we're
+ * cleaning up an old temporary relation for which RemovePgTempFiles has
+ * already recovered the physical storage.
 */
 void
 smgrDoPendingDeletes(bool isCommit)
@ -322,14 +328,11 @@ smgrDoPendingDeletes(bool isCommit)
 				SMgrRelation srel;
 				int			i;

-				srel = smgropen(pending->relnode);
+				srel = smgropen(pending->relnode, pending->backend);
 				for (i = 0; i <= MAX_FORKNUM; i++)
 				{
 					if (smgrexists(srel, i))
-						smgrdounlink(srel,
-									 i,
-									 pending->isTemp,
-									 false);
+						smgrdounlink(srel, i, false);
 				}
 				smgrclose(srel);
 			}
@ -341,20 +344,24 @@ smgrDoPendingDeletes(bool isCommit)
 }

 /*
- * smgrGetPendingDeletes() -- Get a list of relations to be deleted.
+ * smgrGetPendingDeletes() -- Get a list of non-temp relations to be deleted.
 *
 * The return value is the number of relations scheduled for termination.
 * *ptr is set to point to a freshly-palloc'd array of RelFileNodes.
 * If there are no relations to be deleted, *ptr is set to NULL.
 *
- * If haveNonTemp isn't NULL, the bool it points to gets set to true if
- * there is any non-temp table pending to be deleted; false if not.
+ * Only non-temporary relations are included in the returned list.  This is OK
+ * because the list is used only in contexts where temporary relations don't
+ * matter: we're either writing to the two-phase state file (and transactions
+ * that have touched temp tables can't be prepared) or we're writing to xlog
+ * (and all temporary files will be zapped if we restart anyway, so no need
+ * for redo to do it also).
 *
 * Note that the list does not include anything scheduled for termination
 * by upper-level transactions.
 */
 int
-smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr, bool *haveNonTemp)
+smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr)
 {
 	int			nestLevel = GetCurrentTransactionNestLevel();
 	int			nrels;
@ -362,11 +369,10 @@ smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr, bool *haveNonTemp)
 	PendingRelDelete *pending;

 	nrels = 0;
-	if (haveNonTemp)
-		*haveNonTemp = false;
 	for (pending = pendingDeletes; pending != NULL; pending = pending->next)
 	{
-		if (pending->nestLevel >= nestLevel && pending->atCommit == forCommit)
+		if (pending->nestLevel >= nestLevel && pending->atCommit == forCommit
+			&& pending->backend == InvalidBackendId)
 			nrels++;
 	}
 	if (nrels == 0)
@ -378,13 +384,12 @@ smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr, bool *haveNonTemp)
 	*ptr = rptr;
 	for (pending = pendingDeletes; pending != NULL; pending = pending->next)
 	{
-		if (pending->nestLevel >= nestLevel && pending->atCommit == forCommit)
+		if (pending->nestLevel >= nestLevel && pending->atCommit == forCommit
+			&& pending->backend == InvalidBackendId)
 		{
 			*rptr = pending->relnode;
 			rptr++;
 		}
-		if (haveNonTemp && !pending->isTemp)
-			*haveNonTemp = true;
 	}
 	return nrels;
 }
@ -456,7 +461,7 @@ smgr_redo(XLogRecPtr lsn, XLogRecord *record)
 		xl_smgr_create *xlrec = (xl_smgr_create *) XLogRecGetData(record);
 		SMgrRelation reln;

-		reln = smgropen(xlrec->rnode);
+		reln = smgropen(xlrec->rnode, InvalidBackendId);
 		smgrcreate(reln, MAIN_FORKNUM, true);
 	}
 	else if (info == XLOG_SMGR_TRUNCATE)
@ -465,7 +470,7 @@ smgr_redo(XLogRecPtr lsn, XLogRecord *record)
 		SMgrRelation reln;
 		Relation	rel;

-		reln = smgropen(xlrec->rnode);
+		reln = smgropen(xlrec->rnode, InvalidBackendId);

 		/*
 		 * Forcibly create relation if it doesn't exist (which suggests that
@ -475,7 +480,7 @@ smgr_redo(XLogRecPtr lsn, XLogRecord *record)
 		 */
 		smgrcreate(reln, MAIN_FORKNUM, true);

-		smgrtruncate(reln, MAIN_FORKNUM, xlrec->blkno, false);
+		smgrtruncate(reln, MAIN_FORKNUM, xlrec->blkno);

 		/* Also tell xlogutils.c about it */
 		XLogTruncateRelation(xlrec->rnode, MAIN_FORKNUM, xlrec->blkno);
@ -502,7 +507,7 @@ smgr_desc(StringInfo buf, uint8 xl_info, char *rec)
 	if (info == XLOG_SMGR_CREATE)
 	{
 		xl_smgr_create *xlrec = (xl_smgr_create *) rec;
-		char	   *path = relpath(xlrec->rnode, MAIN_FORKNUM);
+		char	   *path = relpathperm(xlrec->rnode, MAIN_FORKNUM);

 		appendStringInfo(buf, "file create: %s", path);
 		pfree(path);
@ -510,7 +515,7 @@ smgr_desc(StringInfo buf, uint8 xl_info, char *rec)
 	else if (info == XLOG_SMGR_TRUNCATE)
 	{
 		xl_smgr_truncate *xlrec = (xl_smgr_truncate *) rec;
-		char	   *path = relpath(xlrec->rnode, MAIN_FORKNUM);
+		char	   *path = relpathperm(xlrec->rnode, MAIN_FORKNUM);

 		appendStringInfo(buf, "file truncate: %s to %u blocks", path,
 						 xlrec->blkno);
--- a/src/backend/catalog/toasting.c
+++ b/src/backend/catalog/toasting.c
@ -8,7 +8,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/toasting.c,v 1.33 2010/07/25 23:21:21 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/toasting.c,v 1.34 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -195,7 +195,7 @@ create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid, Datum reloptio
 	 * Toast tables for regular relations go in pg_toast; those for temp
 	 * relations go into the per-backend temp-toast-table namespace.
 	 */
-	if (rel->rd_islocaltemp)
+	if (rel->rd_backend == MyBackendId)
 		namespaceid = GetTempToastNamespace();
 	else
 		namespaceid = PG_TOAST_NAMESPACE;
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.328 2010/07/22 00:47:52 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.329 2010/08/13 20:10:50 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -1019,7 +1019,7 @@ DoCopy(const CopyStmt *stmt, const char *queryString)
 		ExecCheckRTPerms(list_make1(rte), true);

 		/* check read-only transaction */
-		if (XactReadOnly && is_from && !cstate->rel->rd_islocaltemp)
+		if (XactReadOnly && is_from && cstate->rel->rd_backend != MyBackendId)
 			PreventCommandIfReadOnly("COPY FROM");

 		/* Don't allow COPY w/ OIDs to or from a table without them */
--- a/src/backend/commands/sequence.c
+++ b/src/backend/commands/sequence.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/sequence.c,v 1.169 2010/07/25 23:21:21 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/sequence.c,v 1.170 2010/08/13 20:10:51 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -472,7 +472,7 @@ nextval_internal(Oid relid)
 						RelationGetRelationName(seqrel))));

 	/* read-only transactions may only modify temp sequences */
-	if (!seqrel->rd_islocaltemp)
+	if (seqrel->rd_backend != MyBackendId)
 		PreventCommandIfReadOnly("nextval()");

 	if (elm->last != elm->cached)		/* some numbers were cached */
@ -749,7 +749,7 @@ do_setval(Oid relid, int64 next, bool iscalled)
 						RelationGetRelationName(seqrel))));

 	/* read-only transactions may only modify temp sequences */
-	if (!seqrel->rd_islocaltemp)
+	if (seqrel->rd_backend != MyBackendId)
 		PreventCommandIfReadOnly("setval()");

 	/* lock page' buffer and read tuple */
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.339 2010/08/05 14:45:01 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.340 2010/08/13 20:10:51 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -7165,13 +7165,13 @@ ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode)
 	 * Relfilenodes are not unique across tablespaces, so we need to allocate
 	 * a new one in the new tablespace.
 	 */
-	newrelfilenode = GetNewRelFileNode(newTableSpace, NULL);
+	newrelfilenode = GetNewRelFileNode(newTableSpace, NULL, rel->rd_backend);

 	/* Open old and new relation */
 	newrnode = rel->rd_node;
 	newrnode.relNode = newrelfilenode;
 	newrnode.spcNode = newTableSpace;
-	dstrel = smgropen(newrnode);
+	dstrel = smgropen(newrnode, rel->rd_backend);

 	RelationOpenSmgr(rel);

@ -7262,7 +7262,7 @@ copy_relation_data(SMgrRelation src, SMgrRelation dst,

 		/* XLOG stuff */
 		if (use_wal)
-			log_newpage(&dst->smgr_rnode, forkNum, blkno, page);
+			log_newpage(&dst->smgr_rnode.node, forkNum, blkno, page);

 		/*
 		 * Now write the page.	We say isTemp = true even if it's not a temp
--- a/src/backend/postmaster/bgwriter.c
+++ b/src/backend/postmaster/bgwriter.c
@ -38,7 +38,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/postmaster/bgwriter.c,v 1.68 2010/04/28 16:54:15 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/postmaster/bgwriter.c,v 1.69 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -113,7 +113,7 @@
 */
 typedef struct
 {
-	RelFileNode rnode;
+	RelFileNodeBackend rnode;
 	ForkNumber	forknum;
 	BlockNumber segno;			/* see md.c for special values */
 	/* might add a real request-type field later; not needed yet */
@ -1071,7 +1071,8 @@ RequestCheckpoint(int flags)
 * than we have to here.
 */
 bool
-ForwardFsyncRequest(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
+ForwardFsyncRequest(RelFileNodeBackend rnode, ForkNumber forknum,
+					BlockNumber segno)
 {
 	BgWriterRequest *request;

--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.256 2010/02/26 02:00:59 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.257 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -95,7 +95,8 @@ static void WaitIO(volatile BufferDesc *buf);
 static bool StartBufferIO(volatile BufferDesc *buf, bool forInput);
 static void TerminateBufferIO(volatile BufferDesc *buf, bool clear_dirty,
 				  int set_flag_bits);
-static void buffer_write_error_callback(void *arg);
+static void shared_buffer_write_error_callback(void *arg);
+static void local_buffer_write_error_callback(void *arg);
 static volatile BufferDesc *BufferAlloc(SMgrRelation smgr, ForkNumber forkNum,
 			BlockNumber blockNum,
 			BufferAccessStrategy strategy,
@ -141,7 +142,8 @@ PrefetchBuffer(Relation reln, ForkNumber forkNum, BlockNumber blockNum)
 		int			buf_id;

 		/* create a tag so we can lookup the buffer */
-		INIT_BUFFERTAG(newTag, reln->rd_smgr->smgr_rnode, forkNum, blockNum);
+		INIT_BUFFERTAG(newTag, reln->rd_smgr->smgr_rnode.node,
+					   forkNum, blockNum);

 		/* determine its hash code and partition lock ID */
 		newHash = BufTableHashCode(&newTag);
@ -251,18 +253,21 @@ ReadBufferExtended(Relation reln, ForkNumber forkNum, BlockNumber blockNum,
 * ReadBufferWithoutRelcache -- like ReadBufferExtended, but doesn't require
 *		a relcache entry for the relation.
 *
- * NB: caller is assumed to know what it's doing if isTemp is true.
+ * NB: At present, this function may not be used on temporary relations, which
+ * is OK, because we only use it during XLOG replay.  If in the future we
+ * want to use it on temporary relations, we could pass the backend ID as an
+ * additional parameter.
 */
 Buffer
-ReadBufferWithoutRelcache(RelFileNode rnode, bool isTemp,
-						  ForkNumber forkNum, BlockNumber blockNum,
-						  ReadBufferMode mode, BufferAccessStrategy strategy)
+ReadBufferWithoutRelcache(RelFileNode rnode, ForkNumber forkNum,
+						  BlockNumber blockNum, ReadBufferMode mode,
+						  BufferAccessStrategy strategy)
 {
 	bool		hit;

-	SMgrRelation smgr = smgropen(rnode);
+	SMgrRelation smgr = smgropen(rnode, InvalidBackendId);

-	return ReadBuffer_common(smgr, isTemp, forkNum, blockNum, mode, strategy,
+	return ReadBuffer_common(smgr, false, forkNum, blockNum, mode, strategy,
 							 &hit);
 }

@ -414,7 +419,7 @@ ReadBuffer_common(SMgrRelation smgr, bool isLocalBuf, ForkNumber forkNum,
 	{
 		/* new buffers are zero-filled */
 		MemSet((char *) bufBlock, 0, BLCKSZ);
-		smgrextend(smgr, forkNum, blockNum, (char *) bufBlock, isLocalBuf);
+		smgrextend(smgr, forkNum, blockNum, (char *) bufBlock, false);
 	}
 	else
 	{
@ -465,10 +470,10 @@ ReadBuffer_common(SMgrRelation smgr, bool isLocalBuf, ForkNumber forkNum,
 		VacuumCostBalance += VacuumCostPageMiss;

 	TRACE_POSTGRESQL_BUFFER_READ_DONE(forkNum, blockNum,
-									  smgr->smgr_rnode.spcNode,
-									  smgr->smgr_rnode.dbNode,
-									  smgr->smgr_rnode.relNode,
-									  isLocalBuf,
+									  smgr->smgr_rnode.node.spcNode,
+									  smgr->smgr_rnode.node.dbNode,
+									  smgr->smgr_rnode.node.relNode,
+									  smgr->smgr_rnode.backend,
 									  isExtend,
 									  found);

@ -512,7 +517,7 @@ BufferAlloc(SMgrRelation smgr, ForkNumber forkNum,
 	bool		valid;

 	/* create a tag so we can lookup the buffer */
-	INIT_BUFFERTAG(newTag, smgr->smgr_rnode, forkNum, blockNum);
+	INIT_BUFFERTAG(newTag, smgr->smgr_rnode.node, forkNum, blockNum);

 	/* determine its hash code and partition lock ID */
 	newHash = BufTableHashCode(&newTag);
@ -1693,21 +1698,24 @@ PrintBufferLeakWarning(Buffer buffer)
 	volatile BufferDesc *buf;
 	int32		loccount;
 	char	   *path;
+	BackendId	backend;

 	Assert(BufferIsValid(buffer));
 	if (BufferIsLocal(buffer))
 	{
 		buf = &LocalBufferDescriptors[-buffer - 1];
 		loccount = LocalRefCount[-buffer - 1];
+		backend = MyBackendId;
 	}
 	else
 	{
 		buf = &BufferDescriptors[buffer - 1];
 		loccount = PrivateRefCount[buffer - 1];
+		backend = InvalidBackendId;
 	}

 	/* theoretically we should lock the bufhdr here */
-	path = relpath(buf->tag.rnode, buf->tag.forkNum);
+	path = relpathbackend(buf->tag.rnode, backend, buf->tag.forkNum);
 	elog(WARNING,
 		 "buffer refcount leak: [%03d] "
 		 "(rel=%s, blockNum=%u, flags=0x%x, refcount=%u %d)",
@ -1831,14 +1839,14 @@ FlushBuffer(volatile BufferDesc *buf, SMgrRelation reln)
 		return;

 	/* Setup error traceback support for ereport() */
-	errcontext.callback = buffer_write_error_callback;
+	errcontext.callback = shared_buffer_write_error_callback;
 	errcontext.arg = (void *) buf;
 	errcontext.previous = error_context_stack;
 	error_context_stack = &errcontext;

 	/* Find smgr relation for buffer */
 	if (reln == NULL)
-		reln = smgropen(buf->tag.rnode);
+		reln = smgropen(buf->tag.rnode, InvalidBackendId);

 	TRACE_POSTGRESQL_BUFFER_FLUSH_START(buf->tag.forkNum,
 										buf->tag.blockNum,
@ -1929,14 +1937,15 @@ RelationGetNumberOfBlocks(Relation relation)
 * --------------------------------------------------------------------
 */
 void
-DropRelFileNodeBuffers(RelFileNode rnode, ForkNumber forkNum, bool istemp,
+DropRelFileNodeBuffers(RelFileNodeBackend rnode, ForkNumber forkNum,
 					   BlockNumber firstDelBlock)
 {
 	int			i;

-	if (istemp)
+	if (rnode.backend != InvalidBackendId)
 	{
-		DropRelFileNodeLocalBuffers(rnode, forkNum, firstDelBlock);
+		if (rnode.backend == MyBackendId)
+			DropRelFileNodeLocalBuffers(rnode.node, forkNum, firstDelBlock);
 		return;
 	}

@ -1945,7 +1954,7 @@ DropRelFileNodeBuffers(RelFileNode rnode, ForkNumber forkNum, bool istemp,
 		volatile BufferDesc *bufHdr = &BufferDescriptors[i];

 		LockBufHdr(bufHdr);
-		if (RelFileNodeEquals(bufHdr->tag.rnode, rnode) &&
+		if (RelFileNodeEquals(bufHdr->tag.rnode, rnode.node) &&
 			bufHdr->tag.forkNum == forkNum &&
 			bufHdr->tag.blockNum >= firstDelBlock)
 			InvalidateBuffer(bufHdr);	/* releases spinlock */
@ -2008,7 +2017,7 @@ PrintBufferDescs(void)
 			 "[%02d] (freeNext=%d, rel=%s, "
 			 "blockNum=%u, flags=0x%x, refcount=%u %d)",
 			 i, buf->freeNext,
-			 relpath(buf->tag.rnode, buf->tag.forkNum),
+			 relpathbackend(buf->tag.rnode, InvalidBackendId, buf->tag.forkNum),
 			 buf->tag.blockNum, buf->flags,
 			 buf->refcount, PrivateRefCount[i]);
 	}
@ -2078,7 +2087,7 @@ FlushRelationBuffers(Relation rel)
 				ErrorContextCallback errcontext;

 				/* Setup error traceback support for ereport() */
-				errcontext.callback = buffer_write_error_callback;
+				errcontext.callback = local_buffer_write_error_callback;
 				errcontext.arg = (void *) bufHdr;
 				errcontext.previous = error_context_stack;
 				error_context_stack = &errcontext;
@ -2087,7 +2096,7 @@ FlushRelationBuffers(Relation rel)
 						  bufHdr->tag.forkNum,
 						  bufHdr->tag.blockNum,
 						  (char *) LocalBufHdrGetBlock(bufHdr),
-						  true);
+						  false);

 				bufHdr->flags &= ~(BM_DIRTY | BM_JUST_DIRTIED);

@ -2699,8 +2708,9 @@ AbortBufferIO(void)
 			if (sv_flags & BM_IO_ERROR)
 			{
 				/* Buffer is pinned, so we can read tag without spinlock */
-				char	   *path = relpath(buf->tag.rnode, buf->tag.forkNum);
+				char	   *path;

+				path = relpathperm(buf->tag.rnode, buf->tag.forkNum);
 				ereport(WARNING,
 						(errcode(ERRCODE_IO_ERROR),
 						 errmsg("could not write block %u of %s",
@ -2714,17 +2724,36 @@ AbortBufferIO(void)
 }

 /*
- * Error context callback for errors occurring during buffer writes.
+ * Error context callback for errors occurring during shared buffer writes.
 */
 static void
-buffer_write_error_callback(void *arg)
+shared_buffer_write_error_callback(void *arg)
 {
 	volatile BufferDesc *bufHdr = (volatile BufferDesc *) arg;

 	/* Buffer is pinned, so we can read the tag without locking the spinlock */
 	if (bufHdr != NULL)
 	{
-		char	   *path = relpath(bufHdr->tag.rnode, bufHdr->tag.forkNum);
+		char	   *path = relpathperm(bufHdr->tag.rnode, bufHdr->tag.forkNum);
+
+		errcontext("writing block %u of relation %s",
+				   bufHdr->tag.blockNum, path);
+		pfree(path);
+	}
+}
+
+/*
+ * Error context callback for errors occurring during local buffer writes.
+ */
+static void
+local_buffer_write_error_callback(void *arg)
+{
+	volatile BufferDesc *bufHdr = (volatile BufferDesc *) arg;
+
+	if (bufHdr != NULL)
+	{
+		char	   *path = relpathbackend(bufHdr->tag.rnode, MyBackendId,
+										 bufHdr->tag.forkNum);

 		errcontext("writing block %u of relation %s",
 				   bufHdr->tag.blockNum, path);
--- a/src/backend/storage/buffer/localbuf.c
+++ b/src/backend/storage/buffer/localbuf.c
@ -9,7 +9,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.89 2010/01/02 16:57:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.90 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -68,7 +68,7 @@ LocalPrefetchBuffer(SMgrRelation smgr, ForkNumber forkNum,
 	BufferTag	newTag;			/* identity of requested block */
 	LocalBufferLookupEnt *hresult;

-	INIT_BUFFERTAG(newTag, smgr->smgr_rnode, forkNum, blockNum);
+	INIT_BUFFERTAG(newTag, smgr->smgr_rnode.node, forkNum, blockNum);

 	/* Initialize local buffers if first request in this session */
 	if (LocalBufHash == NULL)
@ -110,7 +110,7 @@ LocalBufferAlloc(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum,
 	int			trycounter;
 	bool		found;

-	INIT_BUFFERTAG(newTag, smgr->smgr_rnode, forkNum, blockNum);
+	INIT_BUFFERTAG(newTag, smgr->smgr_rnode.node, forkNum, blockNum);

 	/* Initialize local buffers if first request in this session */
 	if (LocalBufHash == NULL)
@ -127,7 +127,7 @@ LocalBufferAlloc(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum,
 		Assert(BUFFERTAGS_EQUAL(bufHdr->tag, newTag));
 #ifdef LBDEBUG
 		fprintf(stderr, "LB ALLOC (%u,%d,%d) %d\n",
-				smgr->smgr_rnode.relNode, forkNum, blockNum, -b - 1);
+				smgr->smgr_rnode.node.relNode, forkNum, blockNum, -b - 1);
 #endif
 		/* this part is equivalent to PinBuffer for a shared buffer */
 		if (LocalRefCount[b] == 0)
@ -150,7 +150,8 @@ LocalBufferAlloc(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum,

 #ifdef LBDEBUG
 	fprintf(stderr, "LB ALLOC (%u,%d,%d) %d\n",
-		 smgr->smgr_rnode.relNode, forkNum, blockNum, -nextFreeLocalBuf - 1);
+		 smgr->smgr_rnode.node.relNode, forkNum, blockNum,
+		 -nextFreeLocalBuf - 1);
 #endif

 	/*
@ -198,14 +199,14 @@ LocalBufferAlloc(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum,
 		SMgrRelation oreln;

 		/* Find smgr relation for buffer */
-		oreln = smgropen(bufHdr->tag.rnode);
+		oreln = smgropen(bufHdr->tag.rnode, MyBackendId);

 		/* And write... */
 		smgrwrite(oreln,
 				  bufHdr->tag.forkNum,
 				  bufHdr->tag.blockNum,
 				  (char *) LocalBufHdrGetBlock(bufHdr),
-				  true);
+				  false);

 		/* Mark not-dirty now in case we error out below */
 		bufHdr->flags &= ~BM_DIRTY;
@ -309,7 +310,8 @@ DropRelFileNodeLocalBuffers(RelFileNode rnode, ForkNumber forkNum,
 			if (LocalRefCount[i] != 0)
 				elog(ERROR, "block %u of %s is still referenced (local %u)",
 					 bufHdr->tag.blockNum,
-					 relpath(bufHdr->tag.rnode, bufHdr->tag.forkNum),
+					 relpathbackend(bufHdr->tag.rnode, MyBackendId,
+								   bufHdr->tag.forkNum),
 					 LocalRefCount[i]);
 			/* Remove entry from hashtable */
 			hresult = (LocalBufferLookupEnt *)
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/file/fd.c,v 1.157 2010/07/06 22:55:26 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/file/fd.c,v 1.158 2010/08/13 20:10:52 rhaas Exp $
 *
 * NOTES:
 *
@ -249,6 +249,9 @@ static File OpenTemporaryFileInTablespace(Oid tblspcOid, bool rejectError);
 static void AtProcExit_Files(int code, Datum arg);
 static void CleanupTempFiles(bool isProcExit);
 static void RemovePgTempFilesInDir(const char *tmpdirname);
+static void RemovePgTempRelationFiles(const char *tsdirname);
+static void RemovePgTempRelationFilesInDbspace(const char *dbspacedirname);
+static bool looks_like_temp_rel_name(const char *name);


 /*
@ -1824,10 +1827,12 @@ CleanupTempFiles(bool isProcExit)


 /*
- * Remove temporary files left over from a prior postmaster session
+ * Remove temporary and temporary relation files left over from a prior
+ * postmaster session
 *
 * This should be called during postmaster startup.  It will forcibly
- * remove any leftover files created by OpenTemporaryFile.
+ * remove any leftover files created by OpenTemporaryFile and any leftover
+ * temporary relation files created by mdcreate.
 *
 * NOTE: we could, but don't, call this during a post-backend-crash restart
 * cycle.  The argument for not doing it is that someone might want to examine
@ -1847,6 +1852,7 @@ RemovePgTempFiles(void)
 	 */
 	snprintf(temp_path, sizeof(temp_path), "base/%s", PG_TEMP_FILES_DIR);
 	RemovePgTempFilesInDir(temp_path);
+	RemovePgTempRelationFiles("base");

 	/*
 	 * Cycle through temp directories for all non-default tablespaces.
@ -1862,6 +1868,10 @@ RemovePgTempFiles(void)
 		snprintf(temp_path, sizeof(temp_path), "pg_tblspc/%s/%s/%s",
 			spc_de->d_name, TABLESPACE_VERSION_DIRECTORY, PG_TEMP_FILES_DIR);
 		RemovePgTempFilesInDir(temp_path);
+
+		snprintf(temp_path, sizeof(temp_path), "pg_tblspc/%s/%s",
+			spc_de->d_name, TABLESPACE_VERSION_DIRECTORY);
+		RemovePgTempRelationFiles(temp_path);
 	}

 	FreeDir(spc_dir);
@ -1915,3 +1925,123 @@ RemovePgTempFilesInDir(const char *tmpdirname)

 	FreeDir(temp_dir);
 }
+
+/* Process one tablespace directory, look for per-DB subdirectories */
+static void
+RemovePgTempRelationFiles(const char *tsdirname)
+{
+	DIR		   *ts_dir;
+	struct dirent *de;
+	char		dbspace_path[MAXPGPATH];
+
+	ts_dir = AllocateDir(tsdirname);
+	if (ts_dir == NULL)
+	{
+		/* anything except ENOENT is fishy */
+		if (errno != ENOENT)
+			elog(LOG,
+				 "could not open tablespace directory \"%s\": %m",
+				 tsdirname);
+		return;
+	}
+
+	while ((de = ReadDir(ts_dir, tsdirname)) != NULL)
+	{
+		int		i = 0;
+
+		/*
+		 * We're only interested in the per-database directories, which have
+		 * numeric names.  Note that this code will also (properly) ignore "."
+		 * and "..".
+		 */
+		while (isdigit((unsigned char) de->d_name[i]))
+			++i;
+		if (de->d_name[i] != '\0' || i == 0)
+			continue;
+
+		snprintf(dbspace_path, sizeof(dbspace_path), "%s/%s",
+				 tsdirname, de->d_name);
+		RemovePgTempRelationFilesInDbspace(dbspace_path);
+	}
+
+	FreeDir(ts_dir);
+}
+
+/* Process one per-dbspace directory for RemovePgTempRelationFiles */
+static void
+RemovePgTempRelationFilesInDbspace(const char *dbspacedirname)
+{
+	DIR		   *dbspace_dir;
+	struct dirent *de;
+	char		rm_path[MAXPGPATH];
+
+	dbspace_dir = AllocateDir(dbspacedirname);
+	if (dbspace_dir == NULL)
+	{
+		/* we just saw this directory, so it really ought to be there */
+		elog(LOG,
+			 "could not open dbspace directory \"%s\": %m",
+			 dbspacedirname);
+		return;
+	}
+
+	while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
+	{
+		if (!looks_like_temp_rel_name(de->d_name))
+			continue;
+
+		snprintf(rm_path, sizeof(rm_path), "%s/%s",
+				 dbspacedirname, de->d_name);
+
+		unlink(rm_path);	/* note we ignore any error */
+	}
+
+	FreeDir(dbspace_dir);
+}
+
+/* t<digits>_<digits>, or t<digits>_<digits>_<forkname> */
+static bool
+looks_like_temp_rel_name(const char *name)
+{
+	int			pos;
+	int			savepos;
+
+	/* Must start with "t". */
+	if (name[0] != 't')
+		return false;
+
+	/* Followed by a non-empty string of digits and then an underscore. */
+	for (pos = 1; isdigit((unsigned char) name[pos]); ++pos)
+		;
+	if (pos == 1 || name[pos] != '_')
+		return false;
+
+	/* Followed by another nonempty string of digits. */
+	for (savepos = ++pos; isdigit((unsigned char) name[pos]); ++pos)
+		;
+	if (savepos == pos)
+		return false;
+
+	/* We might have _forkname or .segment or both. */
+	if (name[pos] == '_')
+	{
+		int		forkchar = forkname_chars(&name[pos+1]);
+		if (forkchar <= 0)
+			return false;
+		pos += forkchar + 1;
+	}
+	if (name[pos] == '.')
+	{
+		int		segchar;
+		for (segchar = 1; isdigit((unsigned char) name[pos+segchar]); ++segchar)
+			;
+		if (segchar <= 1)
+			return false;
+		pos += segchar;
+	}
+
+	/* Now we should be at the end. */
+	if (name[pos] != '\0')
+		return false;
+	return true;
+}
--- a/src/backend/storage/freespace/freespace.c
+++ b/src/backend/storage/freespace/freespace.c
@ -8,7 +8,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.77 2010/02/26 02:00:59 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.78 2010/08/13 20:10:52 rhaas Exp $
 *
 *
 * NOTES:
@ -303,7 +303,7 @@ FreeSpaceMapTruncateRel(Relation rel, BlockNumber nblocks)
 	}

 	/* Truncate the unused FSM pages, and send smgr inval message */
-	smgrtruncate(rel->rd_smgr, FSM_FORKNUM, new_nfsmblocks, rel->rd_istemp);
+	smgrtruncate(rel->rd_smgr, FSM_FORKNUM, new_nfsmblocks);

 	/*
 	 * We might as well update the local smgr_fsm_nblocks setting.
--- a/src/backend/storage/smgr/md.c
+++ b/src/backend/storage/smgr/md.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/smgr/md.c,v 1.151 2010/02/26 02:01:01 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/smgr/md.c,v 1.152 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -119,7 +119,7 @@ static MemoryContext MdCxt;		/* context for all md.c allocations */
 */
 typedef struct
 {
-	RelFileNode rnode;			/* the targeted relation */
+	RelFileNodeBackend rnode;	/* the targeted relation */
 	ForkNumber	forknum;
 	BlockNumber segno;			/* which segment */
 } PendingOperationTag;
@ -135,7 +135,7 @@ typedef struct

 typedef struct
 {
-	RelFileNode rnode;			/* the dead relation to delete */
+	RelFileNodeBackend rnode;	/* the dead relation to delete */
 	CycleCtr	cycle_ctr;		/* mdckpt_cycle_ctr when request was made */
 } PendingUnlinkEntry;

@ -158,14 +158,14 @@ static MdfdVec *mdopen(SMgrRelation reln, ForkNumber forknum,
 	   ExtensionBehavior behavior);
 static void register_dirty_segment(SMgrRelation reln, ForkNumber forknum,
 					   MdfdVec *seg);
-static void register_unlink(RelFileNode rnode);
+static void register_unlink(RelFileNodeBackend rnode);
 static MdfdVec *_fdvec_alloc(void);
 static char *_mdfd_segpath(SMgrRelation reln, ForkNumber forknum,
 			  BlockNumber segno);
 static MdfdVec *_mdfd_openseg(SMgrRelation reln, ForkNumber forkno,
 			  BlockNumber segno, int oflags);
 static MdfdVec *_mdfd_getseg(SMgrRelation reln, ForkNumber forkno,
-			 BlockNumber blkno, bool isTemp, ExtensionBehavior behavior);
+			 BlockNumber blkno, bool skipFsync, ExtensionBehavior behavior);
 static BlockNumber _mdnblocks(SMgrRelation reln, ForkNumber forknum,
 		   MdfdVec *seg);

@ -321,7 +321,7 @@ mdcreate(SMgrRelation reln, ForkNumber forkNum, bool isRedo)
 * we are usually not in a transaction anymore when this is called.
 */
 void
-mdunlink(RelFileNode rnode, ForkNumber forkNum, bool isRedo)
+mdunlink(RelFileNodeBackend rnode, ForkNumber forkNum, bool isRedo)
 {
 	char	   *path;
 	int			ret;
@ -417,7 +417,7 @@ mdunlink(RelFileNode rnode, ForkNumber forkNum, bool isRedo)
 */
 void
 mdextend(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
-		 char *buffer, bool isTemp)
+		 char *buffer, bool skipFsync)
 {
 	off_t		seekpos;
 	int			nbytes;
@ -440,7 +440,7 @@ mdextend(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 						relpath(reln->smgr_rnode, forknum),
 						InvalidBlockNumber)));

-	v = _mdfd_getseg(reln, forknum, blocknum, isTemp, EXTENSION_CREATE);
+	v = _mdfd_getseg(reln, forknum, blocknum, skipFsync, EXTENSION_CREATE);

 	seekpos = (off_t) BLCKSZ *(blocknum % ((BlockNumber) RELSEG_SIZE));

@ -478,7 +478,7 @@ mdextend(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 				 errhint("Check free disk space.")));
 	}

-	if (!isTemp)
+	if (!skipFsync && !SmgrIsTemp(reln))
 		register_dirty_segment(reln, forknum, v);

 	Assert(_mdnblocks(reln, forknum, v) <= ((BlockNumber) RELSEG_SIZE));
@ -605,9 +605,10 @@ mdread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 	MdfdVec    *v;

 	TRACE_POSTGRESQL_SMGR_MD_READ_START(forknum, blocknum,
-										reln->smgr_rnode.spcNode,
-										reln->smgr_rnode.dbNode,
-										reln->smgr_rnode.relNode);
+										reln->smgr_rnode.node.spcNode,
+										reln->smgr_rnode.node.dbNode,
+										reln->smgr_rnode.node.relNode,
+										reln->smgr_rnode.backend);

 	v = _mdfd_getseg(reln, forknum, blocknum, false, EXTENSION_FAIL);

@ -624,9 +625,10 @@ mdread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 	nbytes = FileRead(v->mdfd_vfd, buffer, BLCKSZ);

 	TRACE_POSTGRESQL_SMGR_MD_READ_DONE(forknum, blocknum,
-									   reln->smgr_rnode.spcNode,
-									   reln->smgr_rnode.dbNode,
-									   reln->smgr_rnode.relNode,
+									   reln->smgr_rnode.node.spcNode,
+									   reln->smgr_rnode.node.dbNode,
+									   reln->smgr_rnode.node.relNode,
+									   reln->smgr_rnode.backend,
 									   nbytes,
 									   BLCKSZ);

@ -666,7 +668,7 @@ mdread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 */
 void
 mdwrite(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
-		char *buffer, bool isTemp)
+		char *buffer, bool skipFsync)
 {
 	off_t		seekpos;
 	int			nbytes;
@ -678,11 +680,12 @@ mdwrite(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 #endif

 	TRACE_POSTGRESQL_SMGR_MD_WRITE_START(forknum, blocknum,
-										 reln->smgr_rnode.spcNode,
-										 reln->smgr_rnode.dbNode,
-										 reln->smgr_rnode.relNode);
+										 reln->smgr_rnode.node.spcNode,
+										 reln->smgr_rnode.node.dbNode,
+										 reln->smgr_rnode.node.relNode,
+										 reln->smgr_rnode.backend);

-	v = _mdfd_getseg(reln, forknum, blocknum, isTemp, EXTENSION_FAIL);
+	v = _mdfd_getseg(reln, forknum, blocknum, skipFsync, EXTENSION_FAIL);

 	seekpos = (off_t) BLCKSZ *(blocknum % ((BlockNumber) RELSEG_SIZE));

@ -697,9 +700,10 @@ mdwrite(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 	nbytes = FileWrite(v->mdfd_vfd, buffer, BLCKSZ);

 	TRACE_POSTGRESQL_SMGR_MD_WRITE_DONE(forknum, blocknum,
-										reln->smgr_rnode.spcNode,
-										reln->smgr_rnode.dbNode,
-										reln->smgr_rnode.relNode,
+										reln->smgr_rnode.node.spcNode,
+										reln->smgr_rnode.node.dbNode,
+										reln->smgr_rnode.node.relNode,
+										reln->smgr_rnode.backend,
 										nbytes,
 										BLCKSZ);

@ -720,7 +724,7 @@ mdwrite(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 				 errhint("Check free disk space.")));
 	}

-	if (!isTemp)
+	if (!skipFsync && !SmgrIsTemp(reln))
 		register_dirty_segment(reln, forknum, v);
 }

@ -794,8 +798,7 @@ mdnblocks(SMgrRelation reln, ForkNumber forknum)
 *	mdtruncate() -- Truncate relation to specified number of blocks.
 */
 void
-mdtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks,
-		   bool isTemp)
+mdtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks)
 {
 	MdfdVec    *v;
 	BlockNumber curnblk;
@ -839,7 +842,7 @@ mdtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks,
 						 errmsg("could not truncate file \"%s\": %m",
 								FilePathName(v->mdfd_vfd))));

-			if (!isTemp)
+			if (!SmgrIsTemp(reln))
 				register_dirty_segment(reln, forknum, v);
 			v = v->mdfd_chain;
 			Assert(ov != reln->md_fd[forknum]); /* we never drop the 1st
@ -864,7 +867,7 @@ mdtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks,
 					errmsg("could not truncate file \"%s\" to %u blocks: %m",
 						   FilePathName(v->mdfd_vfd),
 						   nblocks)));
-			if (!isTemp)
+			if (!SmgrIsTemp(reln))
 				register_dirty_segment(reln, forknum, v);
 			v = v->mdfd_chain;
 			ov->mdfd_chain = NULL;
@ -1052,7 +1055,8 @@ mdsync(void)
 				 * the relation will have been dirtied through this same smgr
 				 * relation, and so we can save a file open/close cycle.
 				 */
-				reln = smgropen(entry->tag.rnode);
+				reln = smgropen(entry->tag.rnode.node,
+								entry->tag.rnode.backend);

 				/*
 				 * It is possible that the relation has been dropped or
@ -1235,7 +1239,7 @@ register_dirty_segment(SMgrRelation reln, ForkNumber forknum, MdfdVec *seg)
 * a remote pending-ops table.
 */
 static void
-register_unlink(RelFileNode rnode)
+register_unlink(RelFileNodeBackend rnode)
 {
 	if (pendingOpsTable)
 	{
@ -1278,7 +1282,8 @@ register_unlink(RelFileNode rnode)
 * structure for them.)
 */
 void
-RememberFsyncRequest(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
+RememberFsyncRequest(RelFileNodeBackend rnode, ForkNumber forknum,
+					 BlockNumber segno)
 {
 	Assert(pendingOpsTable);

@ -1291,7 +1296,7 @@ RememberFsyncRequest(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
 		hash_seq_init(&hstat, pendingOpsTable);
 		while ((entry = (PendingOperationEntry *) hash_seq_search(&hstat)) != NULL)
 		{
-			if (RelFileNodeEquals(entry->tag.rnode, rnode) &&
+			if (RelFileNodeBackendEquals(entry->tag.rnode, rnode) &&
 				entry->tag.forknum == forknum)
 			{
 				/* Okay, cancel this entry */
@ -1312,7 +1317,7 @@ RememberFsyncRequest(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
 		hash_seq_init(&hstat, pendingOpsTable);
 		while ((entry = (PendingOperationEntry *) hash_seq_search(&hstat)) != NULL)
 		{
-			if (entry->tag.rnode.dbNode == rnode.dbNode)
+			if (entry->tag.rnode.node.dbNode == rnode.node.dbNode)
 			{
 				/* Okay, cancel this entry */
 				entry->canceled = true;
@ -1326,7 +1331,7 @@ RememberFsyncRequest(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
 			PendingUnlinkEntry *entry = (PendingUnlinkEntry *) lfirst(cell);

 			next = lnext(cell);
-			if (entry->rnode.dbNode == rnode.dbNode)
+			if (entry->rnode.node.dbNode == rnode.node.dbNode)
 			{
 				pendingUnlinks = list_delete_cell(pendingUnlinks, cell, prev);
 				pfree(entry);
@ -1393,7 +1398,7 @@ RememberFsyncRequest(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
 * ForgetRelationFsyncRequests -- forget any fsyncs for a rel
 */
 void
-ForgetRelationFsyncRequests(RelFileNode rnode, ForkNumber forknum)
+ForgetRelationFsyncRequests(RelFileNodeBackend rnode, ForkNumber forknum)
 {
 	if (pendingOpsTable)
 	{
@ -1428,11 +1433,12 @@ ForgetRelationFsyncRequests(RelFileNode rnode, ForkNumber forknum)
 void
 ForgetDatabaseFsyncRequests(Oid dbid)
 {
-	RelFileNode rnode;
+	RelFileNodeBackend rnode;

-	rnode.dbNode = dbid;
-	rnode.spcNode = 0;
-	rnode.relNode = 0;
+	rnode.node.dbNode = dbid;
+	rnode.node.spcNode = 0;
+	rnode.node.relNode = 0;
+	rnode.backend = InvalidBackendId;

 	if (pendingOpsTable)
 	{
@ -1523,12 +1529,12 @@ _mdfd_openseg(SMgrRelation reln, ForkNumber forknum, BlockNumber segno,
 *		specified block.
 *
 * If the segment doesn't exist, we ereport, return NULL, or create the
- * segment, according to "behavior".  Note: isTemp need only be correct
- * in the EXTENSION_CREATE case.
+ * segment, according to "behavior".  Note: skipFsync is only used in the
+ * EXTENSION_CREATE case.
 */
 static MdfdVec *
 _mdfd_getseg(SMgrRelation reln, ForkNumber forknum, BlockNumber blkno,
-			 bool isTemp, ExtensionBehavior behavior)
+			 bool skipFsync, ExtensionBehavior behavior)
 {
 	MdfdVec    *v = mdopen(reln, forknum, behavior);
 	BlockNumber targetseg;
@ -1566,7 +1572,7 @@ _mdfd_getseg(SMgrRelation reln, ForkNumber forknum, BlockNumber blkno,

 					mdextend(reln, forknum,
 							 nextsegno * ((BlockNumber) RELSEG_SIZE) - 1,
-							 zerobuf, isTemp);
+							 zerobuf, skipFsync);
 					pfree(zerobuf);
 				}
 				v->mdfd_chain = _mdfd_openseg(reln, forknum, +nextsegno, O_CREAT);
--- a/src/backend/storage/smgr/smgr.c
+++ b/src/backend/storage/smgr/smgr.c
@ -11,7 +11,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/smgr/smgr.c,v 1.121 2010/02/26 02:01:01 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/smgr/smgr.c,v 1.122 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -45,19 +45,19 @@ typedef struct f_smgr
 	void		(*smgr_create) (SMgrRelation reln, ForkNumber forknum,
 											bool isRedo);
 	bool		(*smgr_exists) (SMgrRelation reln, ForkNumber forknum);
-	void		(*smgr_unlink) (RelFileNode rnode, ForkNumber forknum,
+	void		(*smgr_unlink) (RelFileNodeBackend rnode, ForkNumber forknum,
 											bool isRedo);
 	void		(*smgr_extend) (SMgrRelation reln, ForkNumber forknum,
-							BlockNumber blocknum, char *buffer, bool isTemp);
+							BlockNumber blocknum, char *buffer, bool skipFsync);
 	void		(*smgr_prefetch) (SMgrRelation reln, ForkNumber forknum,
 											  BlockNumber blocknum);
 	void		(*smgr_read) (SMgrRelation reln, ForkNumber forknum,
 										  BlockNumber blocknum, char *buffer);
 	void		(*smgr_write) (SMgrRelation reln, ForkNumber forknum,
-							BlockNumber blocknum, char *buffer, bool isTemp);
+							BlockNumber blocknum, char *buffer, bool skipFsync);
 	BlockNumber (*smgr_nblocks) (SMgrRelation reln, ForkNumber forknum);
 	void		(*smgr_truncate) (SMgrRelation reln, ForkNumber forknum,
-										   BlockNumber nblocks, bool isTemp);
+										   BlockNumber nblocks);
 	void		(*smgr_immedsync) (SMgrRelation reln, ForkNumber forknum);
 	void		(*smgr_pre_ckpt) (void);		/* may be NULL */
 	void		(*smgr_sync) (void);	/* may be NULL */
@ -83,8 +83,6 @@ static HTAB *SMgrRelationHash = NULL;

 /* local function prototypes */
 static void smgrshutdown(int code, Datum arg);
-static void smgr_internal_unlink(RelFileNode rnode, ForkNumber forknum,
-					 int which, bool isTemp, bool isRedo);


 /*
@ -131,8 +129,9 @@ smgrshutdown(int code, Datum arg)
 *		This does not attempt to actually open the object.
 */
 SMgrRelation
-smgropen(RelFileNode rnode)
+smgropen(RelFileNode rnode, BackendId backend)
 {
+	RelFileNodeBackend brnode;
 	SMgrRelation reln;
 	bool		found;

@ -142,7 +141,7 @@ smgropen(RelFileNode rnode)
 		HASHCTL		ctl;

 		MemSet(&ctl, 0, sizeof(ctl));
-		ctl.keysize = sizeof(RelFileNode);
+		ctl.keysize = sizeof(RelFileNodeBackend);
 		ctl.entrysize = sizeof(SMgrRelationData);
 		ctl.hash = tag_hash;
 		SMgrRelationHash = hash_create("smgr relation table", 400,
@ -150,8 +149,10 @@ smgropen(RelFileNode rnode)
 	}

 	/* Look up or create an entry */
+	brnode.node = rnode;
+	brnode.backend = backend;
 	reln = (SMgrRelation) hash_search(SMgrRelationHash,
-									  (void *) &rnode,
+									  (void *) &brnode,
 									  HASH_ENTER, &found);

 	/* Initialize it if not present before */
@ -261,7 +262,7 @@ smgrcloseall(void)
 * such entry exists already.
 */
 void
-smgrclosenode(RelFileNode rnode)
+smgrclosenode(RelFileNodeBackend rnode)
 {
 	SMgrRelation reln;

@ -305,8 +306,8 @@ smgrcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo)
 	 * should be here and not in commands/tablespace.c?  But that would imply
 	 * importing a lot of stuff that smgr.c oughtn't know, either.
 	 */
-	TablespaceCreateDbspace(reln->smgr_rnode.spcNode,
-							reln->smgr_rnode.dbNode,
+	TablespaceCreateDbspace(reln->smgr_rnode.node.spcNode,
+							reln->smgr_rnode.node.dbNode,
 							isRedo);

 	(*(smgrsw[reln->smgr_which].smgr_create)) (reln, forknum, isRedo);
@ -323,29 +324,19 @@ smgrcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo)
 *		already.
 */
 void
-smgrdounlink(SMgrRelation reln, ForkNumber forknum, bool isTemp, bool isRedo)
+smgrdounlink(SMgrRelation reln, ForkNumber forknum, bool isRedo)
 {
-	RelFileNode rnode = reln->smgr_rnode;
+	RelFileNodeBackend rnode = reln->smgr_rnode;
 	int			which = reln->smgr_which;

 	/* Close the fork */
 	(*(smgrsw[which].smgr_close)) (reln, forknum);

-	smgr_internal_unlink(rnode, forknum, which, isTemp, isRedo);
-}
-
-/*
- * Shared subroutine that actually does the unlink ...
- */
-static void
-smgr_internal_unlink(RelFileNode rnode, ForkNumber forknum,
-					 int which, bool isTemp, bool isRedo)
-{
 	/*
 	 * Get rid of any remaining buffers for the relation.  bufmgr will just
 	 * drop them without bothering to write the contents.
 	 */
-	DropRelFileNodeBuffers(rnode, forknum, isTemp, 0);
+	DropRelFileNodeBuffers(rnode, forknum, 0);

 	/*
 	 * It'd be nice to tell the stats collector to forget it immediately, too.
@ -385,10 +376,10 @@ smgr_internal_unlink(RelFileNode rnode, ForkNumber forknum,
 */
 void
 smgrextend(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
-		   char *buffer, bool isTemp)
+		   char *buffer, bool skipFsync)
 {
 	(*(smgrsw[reln->smgr_which].smgr_extend)) (reln, forknum, blocknum,
-											   buffer, isTemp);
+											   buffer, skipFsync);
 }

 /*
@ -426,16 +417,16 @@ smgrread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 *		on disk at return, only dumped out to the kernel.  However,
 *		provisions will be made to fsync the write before the next checkpoint.
 *
- *		isTemp indicates that the relation is a temp table (ie, is managed
- *		by the local-buffer manager).  In this case no provisions need be
- *		made to fsync the write before checkpointing.
+ *		skipFsync indicates that the caller will make other provisions to
+ *		fsync the relation, so we needn't bother.  Temporary relations also
+ *		do not require fsync.
 */
 void
 smgrwrite(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
-		  char *buffer, bool isTemp)
+		  char *buffer, bool skipFsync)
 {
 	(*(smgrsw[reln->smgr_which].smgr_write)) (reln, forknum, blocknum,
-											  buffer, isTemp);
+											  buffer, skipFsync);
 }

 /*
@ -455,14 +446,13 @@ smgrnblocks(SMgrRelation reln, ForkNumber forknum)
 * The truncation is done immediately, so this can't be rolled back.
 */
 void
-smgrtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks,
-			 bool isTemp)
+smgrtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks)
 {
 	/*
 	 * Get rid of any buffers for the about-to-be-deleted blocks. bufmgr will
 	 * just drop them without bothering to write the contents.
 	 */
-	DropRelFileNodeBuffers(reln->smgr_rnode, forknum, isTemp, nblocks);
+	DropRelFileNodeBuffers(reln->smgr_rnode, forknum, nblocks);

 	/*
 	 * Send a shared-inval message to force other backends to close any smgr
@ -479,8 +469,7 @@ smgrtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks,
 	/*
 	 * Do the truncation.
 	 */
-	(*(smgrsw[reln->smgr_which].smgr_truncate)) (reln, forknum, nblocks,
-												 isTemp);
+	(*(smgrsw[reln->smgr_which].smgr_truncate)) (reln, forknum, nblocks);
 }

 /*
@ -499,7 +488,7 @@ smgrtruncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks,
 *		to use the WAL log for PITR or replication purposes: in that case
 *		we have to make WAL entries as well.)
 *
- *		The preceding writes should specify isTemp = true to avoid
+ *		The preceding writes should specify skipFsync = true to avoid
 *		duplicative fsyncs.
 *
 *		Note that you need to do FlushRelationBuffers() first if there is
--- a/src/backend/utils/adt/dbsize.c
+++ b/src/backend/utils/adt/dbsize.c
@ -5,7 +5,7 @@
 * Copyright (c) 2002-2010, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/dbsize.c,v 1.32 2010/08/05 14:45:04 rhaas Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/dbsize.c,v 1.33 2010/08/13 20:10:52 rhaas Exp $
 *
 */

@ -244,14 +244,14 @@ pg_tablespace_size_name(PG_FUNCTION_ARGS)
 * calculate size of (one fork of) a relation
 */
 static int64
-calculate_relation_size(RelFileNode *rfn, ForkNumber forknum)
+calculate_relation_size(RelFileNode *rfn, BackendId backend, ForkNumber forknum)
 {
 	int64		totalsize = 0;
 	char	   *relationpath;
 	char		pathname[MAXPGPATH];
 	unsigned int segcount = 0;

-	relationpath = relpath(*rfn, forknum);
+	relationpath = relpathbackend(*rfn, backend, forknum);

 	for (segcount = 0;; segcount++)
 	{
@ -291,7 +291,7 @@ pg_relation_size(PG_FUNCTION_ARGS)

 	rel = relation_open(relOid, AccessShareLock);

-	size = calculate_relation_size(&(rel->rd_node),
+	size = calculate_relation_size(&(rel->rd_node), rel->rd_backend,
 							  forkname_to_number(text_to_cstring(forkName)));

 	relation_close(rel, AccessShareLock);
@ -315,12 +315,14 @@ calculate_toast_table_size(Oid toastrelid)

 	/* toast heap size, including FSM and VM size */
 	for (forkNum = 0; forkNum <= MAX_FORKNUM; forkNum++)
-		size += calculate_relation_size(&(toastRel->rd_node), forkNum);
+		size += calculate_relation_size(&(toastRel->rd_node),
+										toastRel->rd_backend, forkNum);

 	/* toast index size, including FSM and VM size */
 	toastIdxRel = relation_open(toastRel->rd_rel->reltoastidxid, AccessShareLock);
 	for (forkNum = 0; forkNum <= MAX_FORKNUM; forkNum++)
-		size += calculate_relation_size(&(toastIdxRel->rd_node), forkNum);
+		size += calculate_relation_size(&(toastIdxRel->rd_node),
+										toastIdxRel->rd_backend, forkNum);

 	relation_close(toastIdxRel, AccessShareLock);
 	relation_close(toastRel, AccessShareLock);
@ -349,7 +351,8 @@ calculate_table_size(Oid relOid)
 	 * heap size, including FSM and VM
 	 */
 	for (forkNum = 0; forkNum <= MAX_FORKNUM; forkNum++)
-		size += calculate_relation_size(&(rel->rd_node), forkNum);
+		size += calculate_relation_size(&(rel->rd_node), rel->rd_backend,
+										forkNum);

 	/*
 	 * Size of toast relation
@ -392,7 +395,9 @@ calculate_indexes_size(Oid relOid)
 			idxRel = relation_open(idxOid, AccessShareLock);

 			for (forkNum = 0; forkNum <= MAX_FORKNUM; forkNum++)
-				size += calculate_relation_size(&(idxRel->rd_node), forkNum);
+				size += calculate_relation_size(&(idxRel->rd_node),
+												idxRel->rd_backend,
+												forkNum);

 			relation_close(idxRel, AccessShareLock);
 		}
@ -563,6 +568,7 @@ pg_relation_filepath(PG_FUNCTION_ARGS)
 	HeapTuple	tuple;
 	Form_pg_class relform;
 	RelFileNode rnode;
+	BackendId	backend;
 	char	   *path;

 	tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
@ -600,12 +606,27 @@ pg_relation_filepath(PG_FUNCTION_ARGS)
 			break;
 	}

+	if (!OidIsValid(rnode.relNode))
+	{
+		ReleaseSysCache(tuple);
+		PG_RETURN_NULL();
+	}
+
+	/* If temporary, determine owning backend. */
+	if (!relform->relistemp)
+		backend = InvalidBackendId;
+	else if (isTempOrToastNamespace(relform->relnamespace))
+		backend = MyBackendId;
+	else
+	{
+		/* Do it the hard way. */
+		backend = GetTempNamespaceBackendId(relform->relnamespace);
+		Assert(backend != InvalidBackendId);
+	}
+
 	ReleaseSysCache(tuple);

-	if (!OidIsValid(rnode.relNode))
-		PG_RETURN_NULL();
-
-	path = relpath(rnode, MAIN_FORKNUM);
+	path = relpathbackend(rnode, backend, MAIN_FORKNUM);

 	PG_RETURN_TEXT_P(cstring_to_text(path));
 }
--- a/src/backend/utils/cache/inval.c
+++ b/src/backend/utils/cache/inval.c
@ -80,7 +80,7 @@
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/inval.c,v 1.98 2010/02/26 02:01:11 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/inval.c,v 1.99 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -319,7 +319,8 @@ AddCatcacheInvalidationMessage(InvalidationListHeader *hdr,
 {
 	SharedInvalidationMessage msg;

-	msg.cc.id = (int16) id;
+	Assert(id < CHAR_MAX);
+	msg.cc.id = (int8) id;
 	msg.cc.tuplePtr = *tuplePtr;
 	msg.cc.dbId = dbId;
 	msg.cc.hashValue = hashValue;
@ -513,7 +514,10 @@ LocalExecuteInvalidationMessage(SharedInvalidationMessage *msg)
 		 * We could have smgr entries for relations of other databases, so no
 		 * short-circuit test is possible here.
 		 */
-		smgrclosenode(msg->sm.rnode);
+		RelFileNodeBackend	rnode;
+		rnode.node = msg->sm.rnode;
+		rnode.backend = (msg->sm.backend_hi << 16) | (int) msg->sm.backend_lo;
+		smgrclosenode(rnode);
 	}
 	else if (msg->id == SHAREDINVALRELMAP_ID)
 	{
@ -1163,14 +1167,20 @@ CacheInvalidateRelcacheByRelid(Oid relid)
 * in commit/abort WAL entries.  Instead, calls to CacheInvalidateSmgr()
 * should happen in low-level smgr.c routines, which are executed while
 * replaying WAL as well as when creating it.
+ *
+ * Note: In order to avoid bloating SharedInvalidationMessage, we store only
+ * three bytes of the backend ID using what would otherwise be padding space.
+ * Thus, the maximum possible backend ID is 2^23-1.
 */
 void
-CacheInvalidateSmgr(RelFileNode rnode)
+CacheInvalidateSmgr(RelFileNodeBackend rnode)
 {
 	SharedInvalidationMessage msg;

 	msg.sm.id = SHAREDINVALSMGR_ID;
-	msg.sm.rnode = rnode;
+	msg.sm.backend_hi = rnode.backend >> 16;
+	msg.sm.backend_lo = rnode.backend & 0xffff;
+	msg.sm.rnode = rnode.node;
 	SendSharedInvalidMessages(&msg, 1);
 }

--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@ -8,7 +8,7 @@
 *
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.311 2010/07/06 19:18:58 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.312 2010/08/13 20:10:52 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -858,10 +858,20 @@ RelationBuildDesc(Oid targetRelId, bool insertIt)
 	relation->rd_createSubid = InvalidSubTransactionId;
 	relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
 	relation->rd_istemp = relation->rd_rel->relistemp;
-	if (relation->rd_istemp)
-		relation->rd_islocaltemp = isTempOrToastNamespace(relation->rd_rel->relnamespace);
+	if (!relation->rd_istemp)
+		relation->rd_backend = InvalidBackendId;
+	else if (isTempOrToastNamespace(relation->rd_rel->relnamespace))
+		relation->rd_backend = MyBackendId;
 	else
-		relation->rd_islocaltemp = false;
+	{
+		/*
+		 * If it's a temporary table, but not one of ours, we have to use
+		 * the slow, grotty method to figure out the owning backend.
+		 */
+		relation->rd_backend =
+			GetTempNamespaceBackendId(relation->rd_rel->relnamespace);
+		Assert(relation->rd_backend != InvalidBackendId);
+	}

 	/*
 	 * initialize the tuple descriptor (relation->rd_att).
@ -1424,7 +1434,7 @@ formrdesc(const char *relationName, Oid relationReltype,
 	relation->rd_createSubid = InvalidSubTransactionId;
 	relation->rd_newRelfilenodeSubid = InvalidSubTransactionId;
 	relation->rd_istemp = false;
-	relation->rd_islocaltemp = false;
+	relation->rd_backend = InvalidBackendId;

 	/*
 	 * initialize relation tuple form
@ -2515,7 +2525,7 @@ RelationBuildLocalRelation(const char *relname,

 	/* it is temporary if and only if it is in my temp-table namespace */
 	rel->rd_istemp = isTempOrToastNamespace(relnamespace);
-	rel->rd_islocaltemp = rel->rd_istemp;
+	rel->rd_backend = rel->rd_istemp ? MyBackendId : InvalidBackendId;

 	/*
 	 * create a new tuple descriptor from the one passed in.  We do this
@ -2629,7 +2639,7 @@ void
 RelationSetNewRelfilenode(Relation relation, TransactionId freezeXid)
 {
 	Oid			newrelfilenode;
-	RelFileNode newrnode;
+	RelFileNodeBackend newrnode;
 	Relation	pg_class;
 	HeapTuple	tuple;
 	Form_pg_class classform;
@ -2640,7 +2650,8 @@ RelationSetNewRelfilenode(Relation relation, TransactionId freezeXid)
 		   TransactionIdIsNormal(freezeXid));

 	/* Allocate a new relfilenode */
-	newrelfilenode = GetNewRelFileNode(relation->rd_rel->reltablespace, NULL);
+	newrelfilenode = GetNewRelFileNode(relation->rd_rel->reltablespace, NULL,
+									   relation->rd_backend);

 	/*
 	 * Get a writable copy of the pg_class tuple for the given relation.
@ -2660,9 +2671,10 @@ RelationSetNewRelfilenode(Relation relation, TransactionId freezeXid)
 	 * NOTE: any conflict in relfilenode value will be caught here, if
 	 * GetNewRelFileNode messes up for any reason.
 	 */
-	newrnode = relation->rd_node;
-	newrnode.relNode = newrelfilenode;
-	RelationCreateStorage(newrnode, relation->rd_istemp);
+	newrnode.node = relation->rd_node;
+	newrnode.node.relNode = newrelfilenode;
+	newrnode.backend = relation->rd_backend;
+	RelationCreateStorage(newrnode.node, relation->rd_istemp);
 	smgrclosenode(newrnode);

 	/*
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@ -10,7 +10,7 @@
 * Written by Peter Eisentraut <peter_e@gmx.net>.
 *
 * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.566 2010/08/06 14:51:33 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.567 2010/08/13 20:10:53 rhaas Exp $
 *
 *--------------------------------------------------------------------
 */
@ -96,6 +96,16 @@
 #define MAX_KILOBYTES	(INT_MAX / 1024)
 #endif

+/*
+ * Note: MAX_BACKENDS is limited to 2^23-1 because inval.c stores the
+ * backend ID as a 3-byte signed integer.  Even if that limitation were
+ * removed, we still could not exceed INT_MAX/4 because some places compute
+ * 4*MaxBackends without any overflow check.  This is rechecked in
+ * assign_maxconnections, since MaxBackends is computed as MaxConnections
+ * plus autovacuum_max_workers plus one (for the autovacuum launcher).
+ */
+#define MAX_BACKENDS	0x7fffff
+
 #define KB_PER_MB (1024)
 #define KB_PER_GB (1024*1024)

@ -1414,23 +1424,13 @@ static struct config_int ConfigureNamesInt[] =
 		30 * 1000, -1, INT_MAX / 1000, NULL, NULL
 	},

-	/*
-	 * Note: MaxBackends is limited to INT_MAX/4 because some places compute
-	 * 4*MaxBackends without any overflow check.  This check is made in
-	 * assign_maxconnections, since MaxBackends is computed as MaxConnections
-	 * plus autovacuum_max_workers plus one (for the autovacuum launcher).
-	 *
-	 * Likewise we have to limit NBuffers to INT_MAX/2.
-	 *
-	 * See also CheckRequiredParameterValues() if this parameter changes
-	 */
 	{
 		{"max_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
 			gettext_noop("Sets the maximum number of concurrent connections."),
 			NULL
 		},
 		&MaxConnections,
-		100, 1, INT_MAX / 4, assign_maxconnections, NULL
+		100, 1, MAX_BACKENDS, assign_maxconnections, NULL
 	},

 	{
@ -1439,9 +1439,13 @@ static struct config_int ConfigureNamesInt[] =
 			NULL
 		},
 		&ReservedBackends,
-		3, 0, INT_MAX / 4, NULL, NULL
+		3, 0, MAX_BACKENDS, NULL, NULL
 	},

+	/*
+	 * We sometimes multiply the number of shared buffers by two without
+	 * checking for overflow, so we mustn't allow more than INT_MAX / 2.
+	 */
 	{
 		{"shared_buffers", PGC_POSTMASTER, RESOURCES_MEM,
 			gettext_noop("Sets the number of shared memory buffers used by the server."),
@ -1618,7 +1622,7 @@ static struct config_int ConfigureNamesInt[] =
 			NULL
 		},
 		&max_prepared_xacts,
-		0, 0, INT_MAX / 4, NULL, NULL
+		0, 0, MAX_BACKENDS, NULL, NULL
 	},

 #ifdef LOCK_DEBUG
@ -1782,7 +1786,7 @@ static struct config_int ConfigureNamesInt[] =
 			NULL
 		},
 		&max_wal_senders,
-		0, 0, INT_MAX / 4, NULL, NULL
+		0, 0, MAX_BACKENDS, NULL, NULL
 	},

 	{
@ -2022,7 +2026,7 @@ static struct config_int ConfigureNamesInt[] =
 			NULL
 		},
 		&autovacuum_max_workers,
-		3, 1, INT_MAX / 4, assign_autovacuum_max_workers, NULL
+		3, 1, MAX_BACKENDS, assign_autovacuum_max_workers, NULL
 	},

 	{
@ -7995,7 +7999,7 @@ show_tcp_keepalives_count(void)
 static bool
 assign_maxconnections(int newval, bool doit, GucSource source)
 {
-	if (newval + autovacuum_max_workers + 1 > INT_MAX / 4)
+	if (newval + autovacuum_max_workers + 1 > MAX_BACKENDS)
 		return false;

 	if (doit)
@ -8007,7 +8011,7 @@ assign_maxconnections(int newval, bool doit, GucSource source)
 static bool
 assign_autovacuum_max_workers(int newval, bool doit, GucSource source)
 {
-	if (MaxConnections + newval + 1 > INT_MAX / 4)
+	if (MaxConnections + newval + 1 > MAX_BACKENDS)
 		return false;

 	if (doit)
--- a/src/backend/utils/probes.d
+++ b/src/backend/utils/probes.d
@ -3,7 +3,7 @@
 *
 *	Copyright (c) 2006-2010, PostgreSQL Global Development Group
 *
- *	$PostgreSQL: pgsql/src/backend/utils/probes.d,v 1.12 2010/01/02 16:57:53 momjian Exp $
+ *	$PostgreSQL: pgsql/src/backend/utils/probes.d,v 1.13 2010/08/13 20:10:52 rhaas Exp $
 * ----------
 */

@ -55,7 +55,7 @@ provider postgresql {
 	probe sort__done(bool, long);

 	probe buffer__read__start(ForkNumber, BlockNumber, Oid, Oid, Oid, bool, bool);
-	probe buffer__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, bool, bool, bool);
+	probe buffer__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, bool, bool);
 	probe buffer__flush__start(ForkNumber, BlockNumber, Oid, Oid, Oid);
 	probe buffer__flush__done(ForkNumber, BlockNumber, Oid, Oid, Oid);

@ -81,10 +81,10 @@ provider postgresql {
 	probe twophase__checkpoint__start();
 	probe twophase__checkpoint__done();

-	probe smgr__md__read__start(ForkNumber, BlockNumber, Oid, Oid, Oid);
-	probe smgr__md__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, int);
-	probe smgr__md__write__start(ForkNumber, BlockNumber, Oid, Oid, Oid);
-	probe smgr__md__write__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, int);
+	probe smgr__md__read__start(ForkNumber, BlockNumber, Oid, Oid, Oid, int);
+	probe smgr__md__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, int, int);
+	probe smgr__md__write__start(ForkNumber, BlockNumber, Oid, Oid, Oid, int);
+	probe smgr__md__write__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, int, int);

 	probe xlog__insert(unsigned char, unsigned char);
 	probe xlog__switch();
--- a/src/include/access/xlog_internal.h
+++ b/src/include/access/xlog_internal.h
@ -11,7 +11,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/access/xlog_internal.h,v 1.33 2010/04/28 16:10:43 heikki Exp $
+ * $PostgreSQL: pgsql/src/include/access/xlog_internal.h,v 1.34 2010/08/13 20:10:53 rhaas 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 0xD064	/* can be used as WAL version indicator */
+#define XLOG_PAGE_MAGIC 0xD065	/* can be used as WAL version indicator */

 typedef struct XLogPageHeaderData
 {
--- a/src/include/catalog/catalog.h
+++ b/src/include/catalog/catalog.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/catalog/catalog.h,v 1.49 2010/02/26 02:01:21 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catalog.h,v 1.50 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -25,10 +25,20 @@

 extern const char *forkNames[];
 extern ForkNumber forkname_to_number(char *forkName);
+extern int forkname_chars(const char *str);

-extern char *relpath(RelFileNode rnode, ForkNumber forknum);
+extern char *relpathbackend(RelFileNode rnode, BackendId backend,
+			  ForkNumber forknum);
 extern char *GetDatabasePath(Oid dbNode, Oid spcNode);

+/* First argument is a RelFileNodeBackend */
+#define relpath(rnode, forknum) \
+		relpathbackend((rnode).node, (rnode).backend, (forknum))
+
+/* First argument is a RelFileNode */
+#define relpathperm(rnode, forknum) \
+		relpathbackend((rnode), InvalidBackendId, (forknum))
+
 extern bool IsSystemRelation(Relation relation);
 extern bool IsToastRelation(Relation relation);

@ -45,6 +55,7 @@ extern bool IsSharedRelation(Oid relationId);
 extern Oid	GetNewOid(Relation relation);
 extern Oid GetNewOidWithIndex(Relation relation, Oid indexId,
 				   AttrNumber oidcolumn);
-extern Oid	GetNewRelFileNode(Oid reltablespace, Relation pg_class);
+extern Oid	GetNewRelFileNode(Oid reltablespace, Relation pg_class,
+				  BackendId backend);

 #endif   /* CATALOG_H */
--- a/src/include/catalog/storage.h
+++ b/src/include/catalog/storage.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/catalog/storage.h,v 1.5 2010/02/07 20:48:13 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/storage.h,v 1.6 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -30,8 +30,7 @@ extern void RelationTruncate(Relation rel, BlockNumber nblocks);
 * naming
 */
 extern void smgrDoPendingDeletes(bool isCommit);
-extern int smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr,
-					  bool *haveNonTemp);
+extern int smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr);
 extern void AtSubCommit_smgr(void);
 extern void AtSubAbort_smgr(void);
 extern void PostPrepare_smgr(void);
--- a/src/include/postmaster/bgwriter.h
+++ b/src/include/postmaster/bgwriter.h
@ -5,7 +5,7 @@
 *
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 *
- * $PostgreSQL: pgsql/src/include/postmaster/bgwriter.h,v 1.15 2010/01/02 16:58:08 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/postmaster/bgwriter.h,v 1.16 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -27,7 +27,7 @@ extern void BackgroundWriterMain(void);
 extern void RequestCheckpoint(int flags);
 extern void CheckpointWriteDelay(int flags, double progress);

-extern bool ForwardFsyncRequest(RelFileNode rnode, ForkNumber forknum,
+extern bool ForwardFsyncRequest(RelFileNodeBackend rnode, ForkNumber forknum,
 					BlockNumber segno);
 extern void AbsorbFsyncRequests(void);

--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/storage/bufmgr.h,v 1.124 2010/01/23 16:37:12 sriggs Exp $
+ * $PostgreSQL: pgsql/src/include/storage/bufmgr.h,v 1.125 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -160,7 +160,7 @@ extern Buffer ReadBuffer(Relation reln, BlockNumber blockNum);
 extern Buffer ReadBufferExtended(Relation reln, ForkNumber forkNum,
 				   BlockNumber blockNum, ReadBufferMode mode,
 				   BufferAccessStrategy strategy);
-extern Buffer ReadBufferWithoutRelcache(RelFileNode rnode, bool isTemp,
+extern Buffer ReadBufferWithoutRelcache(RelFileNode rnode,
 						  ForkNumber forkNum, BlockNumber blockNum,
 						  ReadBufferMode mode, BufferAccessStrategy strategy);
 extern void ReleaseBuffer(Buffer buffer);
@ -180,8 +180,8 @@ extern BlockNumber BufferGetBlockNumber(Buffer buffer);
 extern BlockNumber RelationGetNumberOfBlocks(Relation relation);
 extern void FlushRelationBuffers(Relation rel);
 extern void FlushDatabaseBuffers(Oid dbid);
-extern void DropRelFileNodeBuffers(RelFileNode rnode, ForkNumber forkNum,
-					   bool istemp, BlockNumber firstDelBlock);
+extern void DropRelFileNodeBuffers(RelFileNodeBackend rnode,
+					   ForkNumber forkNum, BlockNumber firstDelBlock);
 extern void DropDatabaseBuffers(Oid dbid);

 #ifdef NOT_USED
--- a/src/include/storage/relfilenode.h
+++ b/src/include/storage/relfilenode.h
@ -7,13 +7,15 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/storage/relfilenode.h,v 1.25 2010/02/07 20:48:13 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/storage/relfilenode.h,v 1.26 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
 #ifndef RELFILENODE_H
 #define RELFILENODE_H

+#include "storage/backendid.h"
+
 /*
 * The physical storage of a relation consists of one or more forks. The
 * main fork is always created, but in addition to that there can be
@ -37,7 +39,8 @@ typedef enum ForkNumber

 /*
 * RelFileNode must provide all that we need to know to physically access
- * a relation. Note, however, that a "physical" relation is comprised of
+ * a relation, with the exception of the backend ID, which can be provided
+ * separately. Note, however, that a "physical" relation is comprised of
 * multiple files on the filesystem, as each fork is stored as a separate
 * file, and each fork can be divided into multiple segments. See md.c.
 *
@ -74,14 +77,30 @@ typedef struct RelFileNode
 } RelFileNode;

 /*
- * Note: RelFileNodeEquals compares relNode first since that is most likely
- * to be different in two unequal RelFileNodes.  It is probably redundant
- * to compare spcNode if the other two fields are found equal, but do it
- * anyway to be sure.
+ * Augmenting a relfilenode with the backend ID provides all the information
+ * we need to locate the physical storage.
+ */
+typedef struct RelFileNodeBackend
+{
+	RelFileNode	node;
+	BackendId	backend;
+} RelFileNodeBackend;
+
+/*
+ * Note: RelFileNodeEquals and RelFileNodeBackendEquals compare relNode first
+ * since that is most likely to be different in two unequal RelFileNodes.  It
+ * is probably redundant to compare spcNode if the other fields are found equal,
+ * but do it anyway to be sure.
 */
 #define RelFileNodeEquals(node1, node2) \
 	((node1).relNode == (node2).relNode && \
 	 (node1).dbNode == (node2).dbNode && \
 	 (node1).spcNode == (node2).spcNode)

+#define RelFileNodeBackendEquals(node1, node2) \
+	((node1).node.relNode == (node2).node.relNode && \
+	 (node1).node.dbNode == (node2).node.dbNode && \
+	 (node1).backend == (node2).backend && \
+	 (node1).node.spcNode == (node2).node.spcNode)
+
 #endif   /* RELFILENODE_H */
--- a/src/include/storage/sinval.h
+++ b/src/include/storage/sinval.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/storage/sinval.h,v 1.59 2010/02/26 02:01:28 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/storage/sinval.h,v 1.60 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -26,7 +26,7 @@
 *	* invalidate an smgr cache entry for a specific physical relation
 *	* invalidate the mapped-relation mapping for a given database
 * More types could be added if needed.  The message type is identified by
- * the first "int16" field of the message struct.  Zero or positive means a
+ * the first "int8" field of the message struct.  Zero or positive means a
 * specific-catcache inval message (and also serves as the catcache ID field).
 * Negative values identify the other message types, as per codes below.
 *
@ -63,7 +63,7 @@
 typedef struct
 {
 	/* note: field layout chosen with an eye to alignment concerns */
-	int16		id;				/* cache ID --- must be first */
+	int8		id;				/* cache ID --- must be first */
 	ItemPointerData tuplePtr;	/* tuple identifier in cached relation */
 	Oid			dbId;			/* database ID, or 0 if a shared relation */
 	uint32		hashValue;		/* hash value of key for this catcache */
@ -73,7 +73,7 @@ typedef struct

 typedef struct
 {
-	int16		id;				/* type field --- must be first */
+	int8		id;				/* type field --- must be first */
 	Oid			dbId;			/* database ID, or 0 if a shared catalog */
 	Oid			catId;			/* ID of catalog whose contents are invalid */
 } SharedInvalCatalogMsg;
@ -82,7 +82,7 @@ typedef struct

 typedef struct
 {
-	int16		id;				/* type field --- must be first */
+	int8		id;				/* type field --- must be first */
 	Oid			dbId;			/* database ID, or 0 if a shared relation */
 	Oid			relId;			/* relation ID */
 } SharedInvalRelcacheMsg;
@ -91,21 +91,23 @@ typedef struct

 typedef struct
 {
-	int16		id;				/* type field --- must be first */
-	RelFileNode rnode;			/* physical file ID */
+	int8		id;				/* type field --- must be first */
+	int8		backend_hi;		/* high bits of backend ID, if temprel */
+	uint16		backend_lo;		/* low bits of backend ID, if temprel */
+	RelFileNode rnode;			/* spcNode, dbNode, relNode */
 } SharedInvalSmgrMsg;

 #define SHAREDINVALRELMAP_ID	(-4)

 typedef struct
 {
-	int16		id;				/* type field --- must be first */
+	int8		id;				/* type field --- must be first */
 	Oid			dbId;			/* database ID, or 0 for shared catalogs */
 } SharedInvalRelmapMsg;

 typedef union
 {
-	int16		id;				/* type field --- must be first */
+	int8		id;				/* type field --- must be first */
 	SharedInvalCatcacheMsg cc;
 	SharedInvalCatalogMsg cat;
 	SharedInvalRelcacheMsg rc;
--- a/src/include/storage/smgr.h
+++ b/src/include/storage/smgr.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/storage/smgr.h,v 1.71 2010/02/26 02:01:28 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/storage/smgr.h,v 1.72 2010/08/13 20:10:53 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -16,6 +16,7 @@

 #include "access/xlog.h"
 #include "fmgr.h"
+#include "storage/backendid.h"
 #include "storage/block.h"
 #include "storage/relfilenode.h"

@ -38,7 +39,7 @@
 typedef struct SMgrRelationData
 {
 	/* rnode is the hashtable lookup key, so it must be first! */
-	RelFileNode smgr_rnode;		/* relation physical identifier */
+	RelFileNodeBackend smgr_rnode;		/* relation physical identifier */

 	/* pointer to owning pointer, or NULL if none */
 	struct SMgrRelationData **smgr_owner;
@ -68,28 +69,30 @@ typedef struct SMgrRelationData

 typedef SMgrRelationData *SMgrRelation;

+#define SmgrIsTemp(smgr) \
+	((smgr)->smgr_rnode.backend != InvalidBackendId)

 extern void smgrinit(void);
-extern SMgrRelation smgropen(RelFileNode rnode);
+extern SMgrRelation smgropen(RelFileNode rnode, BackendId backend);
 extern bool smgrexists(SMgrRelation reln, ForkNumber forknum);
 extern void smgrsetowner(SMgrRelation *owner, SMgrRelation reln);
 extern void smgrclose(SMgrRelation reln);
 extern void smgrcloseall(void);
-extern void smgrclosenode(RelFileNode rnode);
+extern void smgrclosenode(RelFileNodeBackend rnode);
 extern void smgrcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo);
 extern void smgrdounlink(SMgrRelation reln, ForkNumber forknum,
-			 bool isTemp, bool isRedo);
+			 bool isRedo);
 extern void smgrextend(SMgrRelation reln, ForkNumber forknum,
-		   BlockNumber blocknum, char *buffer, bool isTemp);
+		   BlockNumber blocknum, char *buffer, bool skipFsync);
 extern void smgrprefetch(SMgrRelation reln, ForkNumber forknum,
 			 BlockNumber blocknum);
 extern void smgrread(SMgrRelation reln, ForkNumber forknum,
 		 BlockNumber blocknum, char *buffer);
 extern void smgrwrite(SMgrRelation reln, ForkNumber forknum,
-		  BlockNumber blocknum, char *buffer, bool isTemp);
+		  BlockNumber blocknum, char *buffer, bool skipFsync);
 extern BlockNumber smgrnblocks(SMgrRelation reln, ForkNumber forknum);
 extern void smgrtruncate(SMgrRelation reln, ForkNumber forknum,
-			 BlockNumber nblocks, bool isTemp);
+			 BlockNumber nblocks);
 extern void smgrimmedsync(SMgrRelation reln, ForkNumber forknum);
 extern void smgrpreckpt(void);
 extern void smgrsync(void);
@ -103,27 +106,28 @@ extern void mdinit(void);
 extern void mdclose(SMgrRelation reln, ForkNumber forknum);
 extern void mdcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo);
 extern bool mdexists(SMgrRelation reln, ForkNumber forknum);
-extern void mdunlink(RelFileNode rnode, ForkNumber forknum, bool isRedo);
+extern void mdunlink(RelFileNodeBackend rnode, ForkNumber forknum, bool isRedo);
 extern void mdextend(SMgrRelation reln, ForkNumber forknum,
-		 BlockNumber blocknum, char *buffer, bool isTemp);
+		 BlockNumber blocknum, char *buffer, bool skipFsync);
 extern void mdprefetch(SMgrRelation reln, ForkNumber forknum,
 		   BlockNumber blocknum);
 extern void mdread(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 	   char *buffer);
 extern void mdwrite(SMgrRelation reln, ForkNumber forknum,
-		BlockNumber blocknum, char *buffer, bool isTemp);
+		BlockNumber blocknum, char *buffer, bool skipFsync);
 extern BlockNumber mdnblocks(SMgrRelation reln, ForkNumber forknum);
 extern void mdtruncate(SMgrRelation reln, ForkNumber forknum,
-		   BlockNumber nblocks, bool isTemp);
+		   BlockNumber nblocks);
 extern void mdimmedsync(SMgrRelation reln, ForkNumber forknum);
 extern void mdpreckpt(void);
 extern void mdsync(void);
 extern void mdpostckpt(void);

 extern void SetForwardFsyncRequests(void);
-extern void RememberFsyncRequest(RelFileNode rnode, ForkNumber forknum,
+extern void RememberFsyncRequest(RelFileNodeBackend rnode, ForkNumber forknum,
 					 BlockNumber segno);
-extern void ForgetRelationFsyncRequests(RelFileNode rnode, ForkNumber forknum);
+extern void ForgetRelationFsyncRequests(RelFileNodeBackend rnode,
+							ForkNumber forknum);
 extern void ForgetDatabaseFsyncRequests(Oid dbid);

 /* smgrtype.c */
--- a/src/include/utils/inval.h
+++ b/src/include/utils/inval.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/utils/inval.h,v 1.49 2010/02/08 04:33:55 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/inval.h,v 1.50 2010/08/13 20:10:54 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -49,7 +49,7 @@ extern void CacheInvalidateRelcacheByTuple(HeapTuple classTuple);

 extern void CacheInvalidateRelcacheByRelid(Oid relid);

-extern void CacheInvalidateSmgr(RelFileNode rnode);
+extern void CacheInvalidateSmgr(RelFileNodeBackend rnode);

 extern void CacheInvalidateRelmap(Oid databaseId);

--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@ -7,7 +7,7 @@
 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
- * $PostgreSQL: pgsql/src/include/utils/rel.h,v 1.124 2010/02/26 02:01:29 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/utils/rel.h,v 1.125 2010/08/13 20:10:54 rhaas Exp $
 *
 *-------------------------------------------------------------------------
 */
@ -126,8 +126,8 @@ typedef struct RelationData
 	/* use "struct" here to avoid needing to include smgr.h: */
 	struct SMgrRelationData *rd_smgr;	/* cached file handle, or NULL */
 	int			rd_refcnt;		/* reference count */
+	BackendId	rd_backend;		/* owning backend id, if temporary relation */
 	bool		rd_istemp;		/* rel is a temporary relation */
-	bool		rd_islocaltemp; /* rel is a temp rel of this session */
 	bool		rd_isnailed;	/* rel is nailed in cache */
 	bool		rd_isvalid;		/* relcache entry is valid */
 	char		rd_indexvalid;	/* state of rd_indexlist: 0 = not valid, 1 =
@ -347,7 +347,7 @@ typedef struct StdRdOptions
 #define RelationOpenSmgr(relation) \
 	do { \
 		if ((relation)->rd_smgr == NULL) \
-			smgrsetowner(&((relation)->rd_smgr), smgropen((relation)->rd_node)); \
+			smgrsetowner(&((relation)->rd_smgr), smgropen((relation)->rd_node, (relation)->rd_backend)); \
 	} while (0)

 /*
@ -393,7 +393,7 @@ typedef struct StdRdOptions
 * Beware of multiple eval of argument
 */
 #define RELATION_IS_LOCAL(relation) \
-	((relation)->rd_islocaltemp || \
+	((relation)->rd_backend == MyBackendId || \
 	 (relation)->rd_createSubid != InvalidSubTransactionId)

 /*
@ -403,7 +403,7 @@ typedef struct StdRdOptions
 * Beware of multiple eval of argument
 */
 #define RELATION_IS_OTHER_TEMP(relation) \
-	((relation)->rd_istemp && !(relation)->rd_islocaltemp)
+	((relation)->rd_istemp && (relation)->rd_backend != MyBackendId)

 /* routines in utils/cache/relcache.c */
 extern void RelationIncrementReferenceCount(Relation rel);