*** pgsql/src/backend/commands/vacuum.c	2008/02/11 19:14:53	1.299.4.4
--- pgsql/src/backend/commands/vacuum.c	2009/11/10 18:01:26	1.299.4.5
***************
*** 13,19 ****
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.299.4.3 2008/01/03 21:25:00 tgl Exp $
   *
   *-------------------------------------------------------------------------
   */
--- 13,19 ----
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.299.4.4 2008/02/11 19:14:53 tgl Exp $
   *
   *-------------------------------------------------------------------------
   */
*************** static void vac_update_dbstats(Oid dbid,
*** 176,185 ****
  static void vac_truncate_clog(TransactionId vacuumXID,
  				  TransactionId frozenXID);
  static bool vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind);
! static void full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt);
  static void scan_heap(VRelStats *vacrelstats, Relation onerel,
  		  VacPageList vacuum_pages, VacPageList fraged_pages);
! static void repair_frag(VRelStats *vacrelstats, Relation onerel,
  			VacPageList vacuum_pages, VacPageList fraged_pages,
  			int nindexes, Relation *Irel);
  static void move_chain_tuple(Relation rel,
--- 176,185 ----
  static void vac_truncate_clog(TransactionId vacuumXID,
  				  TransactionId frozenXID);
  static bool vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind);
! static bool full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt);
  static void scan_heap(VRelStats *vacrelstats, Relation onerel,
  		  VacPageList vacuum_pages, VacPageList fraged_pages);
! static bool repair_frag(VRelStats *vacrelstats, Relation onerel,
  			VacPageList vacuum_pages, VacPageList fraged_pages,
  			int nindexes, Relation *Irel);
  static void move_chain_tuple(Relation rel,
*************** vacuum_rel(Oid relid, VacuumStmt *vacstm
*** 885,890 ****
--- 885,891 ----
  	bool		result;
  	AclId		save_userid;
  	bool		save_secdefcxt;
+ 	bool		heldoff;
  
  	/* Begin a transaction for vacuuming this relation */
  	StartTransactionCommand();
*************** vacuum_rel(Oid relid, VacuumStmt *vacstm
*** 1011,1019 ****
  	 * Do the actual work --- either FULL or "lazy" vacuum
  	 */
  	if (vacstmt->full)
! 		full_vacuum_rel(onerel, vacstmt);
  	else
! 		lazy_vacuum_rel(onerel, vacstmt);
  
  	result = true;				/* did the vacuum */
  
--- 1012,1020 ----
  	 * Do the actual work --- either FULL or "lazy" vacuum
  	 */
  	if (vacstmt->full)
! 		heldoff = full_vacuum_rel(onerel, vacstmt);
  	else
! 		heldoff = lazy_vacuum_rel(onerel, vacstmt);
  
  	result = true;				/* did the vacuum */
  
*************** vacuum_rel(Oid relid, VacuumStmt *vacstm
*** 1029,1034 ****
--- 1030,1039 ----
  	StrategyHintVacuum(false);
  	CommitTransactionCommand();
  
+ 	/* now we can allow interrupts again, if disabled */
+ 	if (heldoff)
+ 		RESUME_INTERRUPTS();
+ 
  	/*
  	 * If the relation has a secondary toast rel, vacuum that too while we
  	 * still hold the session lock on the master table.  Note however that
*************** vacuum_rel(Oid relid, VacuumStmt *vacstm
*** 1067,1074 ****
   *
   *		At entry, we have already established a transaction and opened
   *		and locked the relation.
   */
! static void
  full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt)
  {
  	VacPageListData vacuum_pages;		/* List of pages to vacuum and/or
--- 1072,1082 ----
   *
   *		At entry, we have already established a transaction and opened
   *		and locked the relation.
+  *
+  *		The return value indicates whether this function has held off
+  *		interrupts -- caller must RESUME_INTERRUPTS() after commit if true.
   */
! static bool
  full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt)
  {
  	VacPageListData vacuum_pages;		/* List of pages to vacuum and/or
*************** full_vacuum_rel(Relation onerel, VacuumS
*** 1079,1084 ****
--- 1087,1093 ----
  	int			nindexes,
  				i;
  	VRelStats  *vacrelstats;
+ 	bool		heldoff = false;
  
  	vacuum_set_xid_limits(vacstmt, onerel->rd_rel->relisshared,
  						  &OldestXmin, &FreezeLimit);
*************** full_vacuum_rel(Relation onerel, VacuumS
*** 1120,1127 ****
  	if (fraged_pages.num_pages > 0)
  	{
  		/* Try to shrink heap */
! 		repair_frag(vacrelstats, onerel, &vacuum_pages, &fraged_pages,
! 					nindexes, Irel);
  		vac_close_indexes(nindexes, Irel, NoLock);
  	}
  	else
--- 1129,1136 ----
  	if (fraged_pages.num_pages > 0)
  	{
  		/* Try to shrink heap */
! 		heldoff = repair_frag(vacrelstats, onerel, &vacuum_pages, &fraged_pages,
! 						  	  nindexes, Irel);
  		vac_close_indexes(nindexes, Irel, NoLock);
  	}
  	else
*************** full_vacuum_rel(Relation onerel, VacuumS
*** 1150,1155 ****
--- 1159,1166 ----
  	/* update statistics in pg_class */
  	vac_update_relstats(RelationGetRelid(onerel), vacrelstats->rel_pages,
  						vacrelstats->rel_tuples, vacrelstats->hasindex);
+ 
+ 	return heldoff;
  }
  
  
*************** scan_heap(VRelStats *vacrelstats, Relati
*** 1563,1570 ****
   *		for them after committing (in hack-manner - without losing locks
   *		and freeing memory!) current transaction. It truncates relation
   *		if some end-blocks are gone away.
   */
! static void
  repair_frag(VRelStats *vacrelstats, Relation onerel,
  			VacPageList vacuum_pages, VacPageList fraged_pages,
  			int nindexes, Relation *Irel)
--- 1574,1584 ----
   *		for them after committing (in hack-manner - without losing locks
   *		and freeing memory!) current transaction. It truncates relation
   *		if some end-blocks are gone away.
+  *
+  *		The return value indicates whether this function has held off
+  *		interrupts -- caller must RESUME_INTERRUPTS() after commit if true.
   */
! static bool
  repair_frag(VRelStats *vacrelstats, Relation onerel,
  			VacPageList vacuum_pages, VacPageList fraged_pages,
  			int nindexes, Relation *Irel)
*************** repair_frag(VRelStats *vacrelstats, Rela
*** 1588,1593 ****
--- 1602,1608 ----
  				vacuumed_pages;
  	int			keep_tuples = 0;
  	VacRUsage	ru0;
+ 	bool		heldoff = false;
  
  	vac_init_rusage(&ru0);
  
*************** repair_frag(VRelStats *vacrelstats, Rela
*** 2292,2298 ****
--- 2307,2319 ----
  		 * a lot of extra code to close and re-open the relation, indexes,
  		 * etc.  For now, a quick hack: record status of current
  		 * transaction as committed, and continue.
+ 		 *
+ 		 * We prevent cancel interrupts after this point to mitigate the
+ 		 * problem that you can't abort the transaction now; caller is
+ 		 * responsible for re-enabling them after committing the transaction.
  		 */
+ 		HOLD_INTERRUPTS();
+ 		heldoff = true;
  		RecordTransactionCommit();
  	}
  
*************** repair_frag(VRelStats *vacrelstats, Rela
*** 2491,2496 ****
--- 2512,2519 ----
  		pfree(vacrelstats->vtlinks);
  
  	ExecContext_Finish(&ec);
+ 
+ 	return heldoff;
  }
  
  /*