Revise pgstats stuff to fix the problems with not counting accesses

generated by bitmap index scans.  Along the way, simplify and speed up
the code for counting sequential and index scans; it was both confusing
and inefficient to be taking care of that in the per-tuple loops, IMHO.
initdb forced because of internal changes in pg_stat view definitions.

Author: tglsfdc

doc/src/sgml/monitoring.sgml

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.51 2005/09/22 20:44:36 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.52 2005/10/06 02:29:07 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -17,8 +17,10 @@
 #include "access/itup.h"
 #include "access/gist_private.h"
 #include "executor/execdebug.h"
+#include "pgstat.h"
 #include "utils/memutils.h"
 
+
 static OffsetNumber gistfindnext(IndexScanDesc scan, OffsetNumber n,
 			 ScanDirection dir);
 static int	gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, bool ignore_killed_tuples);
@@ -161,6 +163,8 @@ gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, b
 
 		stk->next = NULL;
 		stk->block = GIST_ROOT_BLKNO;
+
+		pgstat_count_index_scan(&scan->xs_pgstat_info);
 	}
 	else if (so->curbuf == InvalidBuffer)
 	{

src/backend/access/gist/gistget.c

@@ -8,13 +8,14 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/hash/hashsearch.c,v 1.38 2004/12/31 21:59:13 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/hash/hashsearch.c,v 1.39 2005/10/06 02:29:08 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
 
 #include "access/hash.h"
+#include "pgstat.h"
 #include "storage/lmgr.h"
 
 
@@ -130,6 +131,8 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
 	ItemPointer current;
 	OffsetNumber offnum;
 
+	pgstat_count_index_scan(&scan->xs_pgstat_info);
+
 	current = &(scan->currentItemData);
 	ItemPointerSetInvalid(current);
 

src/backend/access/hash/hashsearch.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.198 2005/08/20 00:39:51 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.199 2005/10/06 02:29:10 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -47,10 +47,10 @@
 #include "catalog/catalog.h"
 #include "catalog/namespace.h"
 #include "miscadmin.h"
+#include "pgstat.h"
 #include "storage/procarray.h"
 #include "utils/inval.h"
 #include "utils/relcache.h"
-#include "pgstat.h"
 
 
 static XLogRecPtr log_heap_update(Relation reln, Buffer oldbuf,
@@ -90,6 +90,8 @@ initscan(HeapScanDesc scan, ScanKey key)
 	 */
 	if (key != NULL)
 		memcpy(scan->rs_key, key, scan->rs_nkeys * sizeof(ScanKeyData));
+
+	pgstat_count_heap_scan(&scan->rs_pgstat_info);
 }
 
 /* ----------------
@@ -680,8 +682,6 @@ heap_rescan(HeapScanDesc scan,
 	 * reinitialize scan descriptor
 	 */
 	initscan(scan, key);
-
-	pgstat_reset_heap_scan(&scan->rs_pgstat_info);
 }
 
 /* ----------------
@@ -762,8 +762,6 @@ heap_getnext(HeapScanDesc scan, ScanDirection direction)
 		return NULL;
 	}
 
-	pgstat_count_heap_scan(&scan->rs_pgstat_info);
-
 	/*
 	 * if we get here it means we have a new current scan tuple, so point
 	 * to the proper return buffer and return the tuple.
@@ -927,14 +925,9 @@ heap_release_fetch(Relation relation,
 		 */
 		*userbuf = buffer;
 
-		/*
-		 * Count the successful fetch in *pgstat_info if given, otherwise
-		 * in the relation's default statistics area.
-		 */
+		/* Count the successful fetch in *pgstat_info, if given. */
 		if (pgstat_info != NULL)
 			pgstat_count_heap_fetch(pgstat_info);
-		else
-			pgstat_count_heap_fetch(&relation->pgstat_info);
 
 		return true;
 	}
@@ -1152,8 +1145,6 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 
 	RelationPutHeapTuple(relation, buffer, tup);
 
-	pgstat_count_heap_insert(&relation->pgstat_info);
-
 	/* XLOG stuff */
 	if (relation->rd_istemp)
 	{
@@ -1229,6 +1220,8 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 	 */
 	CacheInvalidateHeapTuple(relation, tup);
 
+	pgstat_count_heap_insert(&relation->pgstat_info);
+
 	return HeapTupleGetOid(tup);
 }
 
@@ -1481,8 +1474,6 @@ heap_delete(Relation relation, ItemPointer tid,
 	if (HeapTupleHasExternal(&tp))
 		heap_tuple_toast_attrs(relation, NULL, &tp);
 
-	pgstat_count_heap_delete(&relation->pgstat_info);
-
 	/*
 	 * Mark tuple for invalidation from system caches at next command
 	 * boundary. We have to do this before WriteBuffer because we need to
@@ -1499,6 +1490,8 @@ heap_delete(Relation relation, ItemPointer tid,
 	if (have_tuple_lock)
 		UnlockTuple(relation, &(tp.t_self), ExclusiveLock);
 
+	pgstat_count_heap_delete(&relation->pgstat_info);
+
 	return HeapTupleMayBeUpdated;
 }
 
@@ -1851,8 +1844,6 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 		newbuf = buffer;
 	}
 
-	pgstat_count_heap_update(&relation->pgstat_info);
-
 	/*
 	 * At this point newbuf and buffer are both pinned and locked, and
 	 * newbuf has enough space for the new tuple.  If they are the same
@@ -1929,6 +1920,8 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 	if (have_tuple_lock)
 		UnlockTuple(relation, &(oldtup.t_self), ExclusiveLock);
 
+	pgstat_count_heap_update(&relation->pgstat_info);
+
 	return HeapTupleMayBeUpdated;
 }
 

src/backend/access/heap/heapam.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/index/indexam.c,v 1.84 2005/06/27 12:45:22 teodor Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/index/indexam.c,v 1.85 2005/10/06 02:29:11 tgl Exp $
  *
  * INTERFACE ROUTINES
  *		index_open		- open an index relation by relation OID
@@ -65,9 +65,9 @@
 
 #include "access/genam.h"
 #include "access/heapam.h"
+#include "pgstat.h"
 #include "utils/relcache.h"
 
-#include "pgstat.h"
 
 /* ----------------------------------------------------------------
  *					macros used in index_ routines
@@ -354,8 +354,6 @@ index_rescan(IndexScanDesc scan, ScanKey key)
 	FunctionCall2(procedure,
 				  PointerGetDatum(scan),
 				  PointerGetDatum(key));
-
-	pgstat_reset_index_scan(&scan->xs_pgstat_info);
 }
 
 /* ----------------
@@ -521,8 +519,6 @@ index_getnext(IndexScanDesc scan, ScanDirection direction)
 	{
 		bool		found;
 
-		pgstat_count_index_scan(&scan->xs_pgstat_info);
-
 		/*
 		 * The AM's gettuple proc finds the next tuple matching the scan
 		 * keys.
@@ -545,6 +541,8 @@ index_getnext(IndexScanDesc scan, ScanDirection direction)
 			return NULL;		/* failure exit */
 		}
 
+		pgstat_count_index_tuples(&scan->xs_pgstat_info, 1);
+
 		/*
 		 * Fetch the heap tuple and see if it matches the snapshot.
 		 */
@@ -583,8 +581,6 @@ index_getnext(IndexScanDesc scan, ScanDirection direction)
 	 * initialized to 0, which is the correct state ("on row").
 	 */
 
-	pgstat_count_index_getnext(&scan->xs_pgstat_info);
-
 	return heapTuple;
 }
 
@@ -621,6 +617,9 @@ index_getnext_indexitem(IndexScanDesc scan,
 									   PointerGetDatum(scan),
 									   Int32GetDatum(direction)));
 
+	if (found)
+		pgstat_count_index_tuples(&scan->xs_pgstat_info, 1);
+
 	return found;
 }
 
@@ -660,6 +659,8 @@ index_getmulti(IndexScanDesc scan,
 									   Int32GetDatum(max_tids),
 									   PointerGetDatum(returned_tids)));
 
+	pgstat_count_index_tuples(&scan->xs_pgstat_info, *returned_tids);
+
 	return found;
 }
 

src/backend/access/index/indexam.c

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.93 2005/06/19 22:41:00 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.94 2005/10/06 02:29:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -17,6 +17,7 @@
 
 #include "access/genam.h"
 #include "access/nbtree.h"
+#include "pgstat.h"
 #include "utils/lsyscache.h"
 
 
@@ -501,6 +502,8 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 	int			i;
 	StrategyNumber strat_total;
 
+	pgstat_count_index_scan(&scan->xs_pgstat_info);
+
 	/*
 	 * Examine the scan keys and eliminate any redundant keys; also
 	 * discover how many keys must be matched to continue the scan.

src/backend/access/nbtree/nbtsearch.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/rtree/rtget.c,v 1.35 2005/03/27 23:53:02 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/rtree/rtget.c,v 1.36 2005/10/06 02:29:14 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -18,6 +18,8 @@
 #include "access/iqual.h"
 #include "access/relscan.h"
 #include "access/rtree.h"
+#include "pgstat.h"
+
 
 static OffsetNumber findnext(IndexScanDesc s, OffsetNumber n,
 		 ScanDirection dir);
@@ -118,6 +120,7 @@ rtnext(IndexScanDesc s, ScanDirection dir)
 		/* first call: start at the root */
 		Assert(BufferIsValid(so->curbuf) == false);
 		so->curbuf = ReadBuffer(s->indexRelation, P_ROOT);
+		pgstat_count_index_scan(&s->xs_pgstat_info);
 	}
 
 	p = BufferGetPage(so->curbuf);

src/backend/access/rtree/rtget.c

@@ -3,7 +3,7 @@
  *
  * Copyright (c) 1996-2005, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/backend/catalog/system_views.sql,v 1.21 2005/08/15 23:00:13 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/catalog/system_views.sql,v 1.22 2005/10/06 02:29:15 tgl Exp $
  */
 
 CREATE VIEW pg_roles AS 
@@ -182,8 +182,9 @@ CREATE VIEW pg_stat_all_tables AS
             C.relname AS relname, 
             pg_stat_get_numscans(C.oid) AS seq_scan, 
             pg_stat_get_tuples_returned(C.oid) AS seq_tup_read, 
-            sum(pg_stat_get_numscans(I.indexrelid)) AS idx_scan, 
-            sum(pg_stat_get_tuples_fetched(I.indexrelid)) AS idx_tup_fetch, 
+            sum(pg_stat_get_numscans(I.indexrelid))::bigint AS idx_scan, 
+            sum(pg_stat_get_tuples_fetched(I.indexrelid))::bigint +
+                    pg_stat_get_tuples_fetched(C.oid) AS idx_tup_fetch, 
             pg_stat_get_tuples_inserted(C.oid) AS n_tup_ins, 
             pg_stat_get_tuples_updated(C.oid) AS n_tup_upd, 
             pg_stat_get_tuples_deleted(C.oid) AS n_tup_del 
@@ -210,8 +211,8 @@ CREATE VIEW pg_statio_all_tables AS
                     pg_stat_get_blocks_hit(C.oid) AS heap_blks_read, 
             pg_stat_get_blocks_hit(C.oid) AS heap_blks_hit, 
             sum(pg_stat_get_blocks_fetched(I.indexrelid) - 
-                    pg_stat_get_blocks_hit(I.indexrelid)) AS idx_blks_read, 
-            sum(pg_stat_get_blocks_hit(I.indexrelid)) AS idx_blks_hit, 
+                    pg_stat_get_blocks_hit(I.indexrelid))::bigint AS idx_blks_read, 
+            sum(pg_stat_get_blocks_hit(I.indexrelid))::bigint AS idx_blks_hit, 
             pg_stat_get_blocks_fetched(T.oid) - 
                     pg_stat_get_blocks_hit(T.oid) AS toast_blks_read, 
             pg_stat_get_blocks_hit(T.oid) AS toast_blks_hit, 
@@ -350,5 +351,5 @@ UPDATE pg_proc SET
                          'bool'],
   proargmodes = ARRAY['i'::"char", 'o', 'o', 'o', 'o', 'o', 'o'],
   proargnames = ARRAY['filename'::text, 'size', 'access', 'modification',
-		      'change', 'creation', 'isdir']
+                      'change', 'creation', 'isdir']
 WHERE oid = 'pg_stat_file(text)'::regprocedure;

src/backend/catalog/system_views.sql

@@ -21,7 +21,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/nodeBitmapHeapscan.c,v 1.2 2005/05/06 17:24:54 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/nodeBitmapHeapscan.c,v 1.3 2005/10/06 02:29:16 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -39,6 +39,7 @@
 #include "executor/execdebug.h"
 #include "executor/nodeBitmapHeapscan.h"
 #include "parser/parsetree.h"
+#include "pgstat.h"
 #include "utils/memutils.h"
 
 
@@ -328,6 +329,9 @@ ExecBitmapHeapReScan(BitmapHeapScanState *node, ExprContext *exprCtxt)
 	/* rescan to release any page pin */
 	heap_rescan(node->ss.ss_currentScanDesc, NULL);
 
+	/* undo bogus "seq scan" count (see notes in ExecInitBitmapHeapScan) */
+	pgstat_discount_heap_scan(&node->ss.ss_currentScanDesc->rs_pgstat_info);
+
 	if (node->tbm)
 		tbm_free(node->tbm);
 	node->tbm = NULL;
@@ -475,6 +479,13 @@ ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate)
 													  0,
 													  NULL);
 
+	/*
+	 * One problem is that heap_beginscan counts a "sequential scan" start,
+	 * when we actually aren't doing any such thing.  Reverse out the added
+	 * scan count.  (Eventually we may want to count bitmap scans separately.)
+	 */
+	pgstat_discount_heap_scan(&scanstate->ss.ss_currentScanDesc->rs_pgstat_info);
+
 	/*
 	 * get the scan type from the relation descriptor.
 	 */