Back out check for unreferenced files.

Heikki Linnakangas

doc/src/sgml/maintenance.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.42 2005/05/02 18:26:52 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.43 2005/05/10 22:27:29 momjian Exp $
 -->
 
 <chapter id="maintenance">
@@ -474,23 +474,6 @@ HINT:  Stop the postmaster and use a standalone backend to VACUUM in "mydb".
   </para>
  </sect1>
 
- <sect1 id="check-files-after-crash">
-  <title>Check files after crash</title>
-
-  <indexterm zone="check-files-after-crash">
-   <primary>stale file</primary>
-  </indexterm>
-
-  <para>
-   <productname>PostgreSQL</productname> recovers automatically after crash
-   using the write-ahead log (see <xref linkend="wal">) and no manual 
-   operations are normally needed. However, if there was a transaction running 
-   when the crash occured that created or dropped a relation, the 
-   transaction might have left a stale file in the data directory. If this 
-   happens, you will get a notice in the log file stating which files can be 
-   deleted.
-  </para>
- </sect1>
 
  <sect1 id="logfile-maintenance">
   <title>Log File Maintenance</title>

src/backend/access/transam/xlog.c

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.190 2005/05/02 18:26:52 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.191 2005/05/10 22:27:29 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -43,7 +43,6 @@
 #include "utils/builtins.h"
 #include "utils/guc.h"
 #include "utils/relcache.h"
-#include "utils/flatfiles.h"
 
 
 /*
@@ -4526,8 +4525,6 @@ StartupXLOG(void)
 
 		CreateCheckPoint(true, true);
 
-		CheckStaleRelFiles();
-
 		/*
 		 * Close down recovery environment
 		 */
@@ -4539,12 +4536,6 @@ StartupXLOG(void)
 		 */
 		remove_backup_label();
 	}
-	else
-	{
-		XLogInitRelationCache();
-		CheckStaleRelFiles();
-		XLogCloseRelationCache();
-	}
 
 	/*
 	 * Preallocate additional log files, if wanted.

src/backend/catalog/catalog.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/catalog.c,v 1.60 2005/05/02 18:26:53 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/catalog.c,v 1.61 2005/05/10 22:27:29 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -106,39 +106,6 @@ GetDatabasePath(Oid dbNode, Oid spcNode)
 	return path;
 }
 
-/*
- * GetTablespacePath	- construct path to a tablespace symbolic link
- *
- * Result is a palloc'd string.
- *
- * XXX this must agree with relpath and GetDatabasePath!
- */
-char *
-GetTablespacePath(Oid spcNode)
-{
-	int			pathlen;
-	char	   *path;
-
-	Assert(spcNode != GLOBALTABLESPACE_OID);
-
-	if (spcNode == DEFAULTTABLESPACE_OID)
-	{
-		/* The default tablespace is {datadir}/base */
-		pathlen = strlen(DataDir) + 5 + 1;
-		path = (char *) palloc(pathlen);
-		snprintf(path, pathlen, "%s/base",
-				 DataDir);
-	}
-	else
-	{
-		/* All other tablespaces have symlinks in pg_tblspc */
-		pathlen = strlen(DataDir) + 11 + OIDCHARS + 1;
-		path = (char *) palloc(pathlen);
-		snprintf(path, pathlen, "%s/pg_tblspc/%u",
-				 DataDir, spcNode);
-	}
-	return path;
-}
 
 /*
  * IsSystemRelation

src/backend/commands/tablespace.c

@@ -37,7 +37,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/tablespace.c,v 1.18 2005/05/02 18:26:53 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/tablespace.c,v 1.19 2005/05/10 22:27:29 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -341,7 +341,8 @@ CreateTableSpace(CreateTableSpaceStmt *stmt)
 	/*
 	 * All seems well, create the symlink
 	 */
-	linkloc = GetTablespacePath(tablespaceoid);
+	linkloc = (char *) palloc(strlen(DataDir) + 11 + 10 + 1);
+	sprintf(linkloc, "%s/pg_tblspc/%u", DataDir, tablespaceoid);
 
 	if (symlink(location, linkloc) < 0)
 		ereport(ERROR,
@@ -494,7 +495,8 @@ remove_tablespace_directories(Oid tablespaceoid, bool redo)
 	char	   *subfile;
 	struct stat st;
 
-	location = GetTablespacePath(tablespaceoid);
+	location = (char *) palloc(strlen(DataDir) + 11 + 10 + 1);
+	sprintf(location, "%s/pg_tblspc/%u", DataDir, tablespaceoid);
 
 	/*
 	 * Check if the tablespace still contains any files.  We try to rmdir
@@ -1034,7 +1036,8 @@ tblspc_redo(XLogRecPtr lsn, XLogRecord *record)
 		set_short_version(location);
 
 		/* Create the symlink if not already present */
-		linkloc = GetTablespacePath(xlrec->ts_id);
+		linkloc = (char *) palloc(strlen(DataDir) + 11 + 10 + 1);
+		sprintf(linkloc, "%s/pg_tblspc/%u", DataDir, xlrec->ts_id);
 
 		if (symlink(location, linkloc) < 0)
 		{

src/backend/utils/adt/misc.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/misc.c,v 1.41 2005/05/02 18:26:53 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/misc.c,v 1.42 2005/05/10 22:27:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -26,7 +26,6 @@
 #include "funcapi.h"
 #include "catalog/pg_type.h"
 #include "catalog/pg_tablespace.h"
-#include "catalog/catalog.h"
 
 #define atooid(x)  ((Oid) strtoul((x), NULL, 10))
 
@@ -145,6 +144,11 @@ pg_tablespace_databases(PG_FUNCTION_ARGS)
 
 		fctx = palloc(sizeof(ts_db_fctx));
 
+		/*
+		 * size = path length + tablespace dirname length + 2 dir sep
+		 * chars + oid + terminator
+		 */
+		fctx->location = (char *) palloc(strlen(DataDir) + 11 + 10 + 1);
 		if (tablespaceOid == GLOBALTABLESPACE_OID)
 		{
 			fctx->dirdesc = NULL;
@@ -153,7 +157,12 @@ pg_tablespace_databases(PG_FUNCTION_ARGS)
 		}
 		else
 		{
-			fctx->location = GetTablespacePath(tablespaceOid);
+			if (tablespaceOid == DEFAULTTABLESPACE_OID)
+				sprintf(fctx->location, "%s/base", DataDir);
+			else
+				sprintf(fctx->location, "%s/pg_tblspc/%u", DataDir,
+						tablespaceOid);
+
 			fctx->dirdesc = AllocateDir(fctx->location);
 
 			if (!fctx->dirdesc)

src/backend/utils/init/Makefile

@@ -4,7 +4,7 @@
 #    Makefile for utils/init
 #
 # IDENTIFICATION
-#    $PostgreSQL: pgsql/src/backend/utils/init/Makefile,v 1.19 2005/05/02 18:26:53 momjian Exp $
+#    $PostgreSQL: pgsql/src/backend/utils/init/Makefile,v 1.20 2005/05/10 22:27:30 momjian Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -12,7 +12,7 @@ subdir = src/backend/utils/init
 top_builddir = ../../../..
 include $(top_builddir)/src/Makefile.global
 
-OBJS = flatfiles.o globals.o miscinit.o postinit.o checkfiles.o
+OBJS = flatfiles.o globals.o miscinit.o postinit.o
 
 all: SUBSYS.o
 

src/backend/utils/init/checkfiles.c

-/*-------------------------------------------------------------------------
- *
- *	checkfiles.c
- *	  check for stale relation files during crash recovery
- *
- *	If a backend crashes while in a transaction that has created or
- *	deleted a relfilenode, a stale file can be left over in the data
- *	directory. This file contains routines to clean up those stale
- *	files on recovery.
- *
- *	This adds a 17% increase in startup cost for 100 empty databases.  bjm
- *	One optimization would be to create a 'dirty' file on a postmaster recovery
- *	and remove the dirty flag only when a clean startup detects no unreferenced
- *	files, and use the 'dirty' flag to determine if we should run this on
- *	a clean startup.
- *
- * $PostgreSQL: pgsql/src/backend/utils/init/checkfiles.c,v 1.2 2005/05/05 22:18:27 tgl Exp $
- *
- *-------------------------------------------------------------------------
- */
-#include "postgres.h"
-
-#include "access/heapam.h"
-#include "access/relscan.h"
-#include "access/skey.h"
-#include "catalog/catalog.h"
-#include "catalog/pg_tablespace.h"
-#include "miscadmin.h"
-#include "storage/fd.h"
-#include "utils/flatfiles.h"
-#include "utils/fmgroids.h"
-#include "utils/resowner.h"
-
-
-static void CheckStaleRelFilesFrom(Oid tablespaceoid, Oid dboid);
-static void CheckStaleRelFilesFromTablespace(Oid tablespaceoid);
-
-/* Like AllocateDir, but ereports on failure */
-static DIR *
-AllocateDirChecked(char *path)
-{
-	DIR		   *dirdesc = AllocateDir(path);
-
-	if (dirdesc == NULL)
-		ereport(ERROR,
-				(errcode_for_file_access(),
-				 errmsg("could not open directory \"%s\": %m",
-						path)));
-	return dirdesc;
-}
-
-/*
- * Scan through all tablespaces for relations left over
- * by aborted transactions.
- */
-void
-CheckStaleRelFiles(void)
-{
-	DIR		   *dirdesc;
-	struct dirent *de;
-	char	   *path;
-	int			pathlen;
-
-	pathlen = strlen(DataDir) + 11 + 1;
-	path = (char *) palloc(pathlen);
-	snprintf(path, pathlen, "%s/pg_tblspc/", DataDir);
-	dirdesc = AllocateDirChecked(path);
-	while ((de = readdir(dirdesc)) != NULL)
-	{
-		char	   *invalid;
-		Oid			tablespaceoid;
-
-		/* Check that the directory name looks like valid tablespace link.	*/
-		tablespaceoid = (Oid) strtol(de->d_name, &invalid, 10);
-		if (invalid[0] == '\0')
-			CheckStaleRelFilesFromTablespace(tablespaceoid);
-	}
-	FreeDir(dirdesc);
-	pfree(path);
-
-	CheckStaleRelFilesFromTablespace(DEFAULTTABLESPACE_OID);
-}
-
-/* Scan a specific tablespace for stale relations */
-static void
-CheckStaleRelFilesFromTablespace(Oid tablespaceoid)
-{
-	DIR		   *dirdesc;
-	struct dirent *de;
-	char	   *path;
-
-	path = GetTablespacePath(tablespaceoid);
-
-	dirdesc = AllocateDirChecked(path);
-	while ((de = readdir(dirdesc)) != NULL)
-	{
-		char	   *invalid;
-		Oid			dboid;
-
-		dboid = (Oid) strtol(de->d_name, &invalid, 10);
-		if (invalid[0] == '\0')
-			CheckStaleRelFilesFrom(tablespaceoid, dboid);
-	}
-	FreeDir(dirdesc);
-	pfree(path);
-}
-
-/* Scan a specific database in a specific tablespace for stale relations.
- *
- * First, pg_class for the database is opened, and the relfilenodes of all
- * relations mentioned there are stored in a hash table.
- *
- * Then the directory is scanned. Every file in the directory that's not
- * found in pg_class (the hash table) is logged.
- */
-static void
-CheckStaleRelFilesFrom(Oid tablespaceoid, Oid dboid)
-{
-	DIR		   *dirdesc;
-	struct dirent *de;
-	HASHCTL		hashctl;
-	HTAB	   *relfilenodeHash;
-	RelFileNode rnode;
-	char	   *path;
-
-	/*
-	 * The entry contents is not used for anything, we just check if an oid is
-	 * in the hash table or not.
-	 */
-	hashctl.keysize = sizeof(Oid);
-	hashctl.entrysize = sizeof(Oid);
-	hashctl.hash = tag_hash;
-	relfilenodeHash = hash_create("relfilenodeHash", 100, &hashctl,
-								  HASH_FUNCTION | HASH_ELEM);
-
-	/* Read all relfilenodes from pg_class into the hash table */
-	{
-		ResourceOwner owner,
-					oldowner;
-		Relation	rel;
-		HeapScanDesc scan;
-		HeapTuple	tuple;
-
-		/* Need a resowner to keep the heapam and buffer code happy */
-		owner = ResourceOwnerCreate(NULL, "CheckStaleRelFiles");
-		oldowner = CurrentResourceOwner;
-		CurrentResourceOwner = owner;
-
-		rnode.spcNode = tablespaceoid;
-		rnode.dbNode = dboid;
-		rnode.relNode = RelationRelationId;
-		rel = XLogOpenRelation(true, 0, rnode);
-
-		scan = heap_beginscan(rel, SnapshotNow, 0, NULL);
-		while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
-		{
-			Form_pg_class classform = (Form_pg_class) GETSTRUCT(tuple);
-
-			hash_search(relfilenodeHash, &classform->relfilenode,
-						HASH_ENTER, NULL);
-		}
-		heap_endscan(scan);
-
-		XLogCloseRelation(rnode);
-		CurrentResourceOwner = oldowner;
-		ResourceOwnerDelete(owner);
-	}
-
-	/* Scan the directory */
-	path = GetDatabasePath(dboid, tablespaceoid);
-
-	dirdesc = AllocateDirChecked(path);
-	while ((de = readdir(dirdesc)) != NULL)
-	{
-		char	   *invalid;
-		Oid			relfilenode;
-
-		relfilenode = strtol(de->d_name, &invalid, 10);
-		if (invalid[0] == '\0')
-		{
-			/*
-			 * Filename was a valid number, check if pg_class knows about it
-			 */
-			if (hash_search(relfilenodeHash, &relfilenode,
-							HASH_FIND, NULL) == NULL)
-			{
-				char	   *filepath;
-
-				rnode.spcNode = tablespaceoid;
-				rnode.dbNode = dboid;
-				rnode.relNode = relfilenode;
-
-				filepath = relpath(rnode);
-				ereport(LOG,
-						(errcode_for_file_access(),
-						 errmsg("table or index file \"%s\" is stale and can safely be removed",
-								filepath)));
-				pfree(filepath);
-			}
-		}
-	}
-	FreeDir(dirdesc);
-	pfree(path);
-	hash_destroy(relfilenodeHash);
-}

src/include/catalog/catalog.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/catalog.h,v 1.31 2005/05/02 18:26:54 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catalog.h,v 1.32 2005/05/10 22:27:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -19,7 +19,6 @@
 
 extern char *relpath(RelFileNode rnode);
 extern char *GetDatabasePath(Oid dbNode, Oid spcNode);
-extern char *GetTablespacePath(Oid spcNode);
 
 extern bool IsSystemRelation(Relation relation);
 extern bool IsToastRelation(Relation relation);

src/include/utils/flatfiles.h

@@ -4,7 +4,7 @@
  *	  Routines for maintaining "flat file" images of the shared catalogs.
  *
  *
- * $PostgreSQL: pgsql/src/include/utils/flatfiles.h,v 1.2 2005/05/02 18:26:54 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/utils/flatfiles.h,v 1.3 2005/05/10 22:27:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -30,7 +30,4 @@ extern void AtEOSubXact_UpdateFlatFiles(bool isCommit,
 
 extern Datum flatfile_update_trigger(PG_FUNCTION_ARGS);
 
-/* from checkfiles.c */
-extern void CheckStaleRelFiles(void);
-
 #endif   /* FLATFILES_H */