From 44023dc5f58168bebd28a6d804bd3fc1dfaa3d11 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Sun, 22 Mar 2009 22:39:05 +0000
Subject: [PATCH] Add isExtend to the parameters of the buffer_read_start and
buffer_read_done DTrace probes, so that ordinary reads can be distinguished
from relation extension operations. Move buffer_read_start probe to before
the smgrnblocks() call that's needed in the isExtend case, since really that
step should be charged as part of the time needed for the extension
operation. (This makes it slightly harder to match the read_start with the
associated read_done, since now you can't match them on blockNumber, but it
should still be possible since isExtend operations on the same relation can
never be interleaved.) Per recent discussion.
In passing, add the page identity (forkNum/blockNum) to the parameters of the
buffer_flush_start/buffer_flush_done probes, which were unaccountably lacking
the info.
---
src/backend/storage/buffer/bufmgr.c | 23 +++++++++++++++--------
src/backend/utils/probes.d | 10 +++++-----
2 files changed, 20 insertions(+), 13 deletions(-)
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 59e61decc0..eac9873428 100644
--- 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 1.247 2009/03/13 17:46:21 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.248 2009/03/22 22:39:05 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -256,15 +256,16 @@ ReadBuffer_common(SMgrRelation smgr, bool isLocalBuf, ForkNumber forkNum,
isExtend = (blockNum == P_NEW);
- /* Substitute proper block number if caller asked for P_NEW */
- if (isExtend)
- blockNum = smgrnblocks(smgr, forkNum);
-
TRACE_POSTGRESQL_BUFFER_READ_START(forkNum, blockNum,
smgr->smgr_rnode.spcNode,
smgr->smgr_rnode.dbNode,
smgr->smgr_rnode.relNode,
- isLocalBuf);
+ isLocalBuf,
+ isExtend);
+
+ /* Substitute proper block number if caller asked for P_NEW */
+ if (isExtend)
+ blockNum = smgrnblocks(smgr, forkNum);
if (isLocalBuf)
{
@@ -318,6 +319,7 @@ ReadBuffer_common(SMgrRelation smgr, bool isLocalBuf, ForkNumber forkNum,
smgr->smgr_rnode.dbNode,
smgr->smgr_rnode.relNode,
isLocalBuf,
+ isExtend,
found);
return BufferDescriptorGetBuffer(bufHdr);
@@ -447,6 +449,7 @@ ReadBuffer_common(SMgrRelation smgr, bool isLocalBuf, ForkNumber forkNum,
smgr->smgr_rnode.dbNode,
smgr->smgr_rnode.relNode,
isLocalBuf,
+ isExtend,
found);
return BufferDescriptorGetBuffer(bufHdr);
@@ -1865,7 +1868,9 @@ FlushBuffer(volatile BufferDesc *buf, SMgrRelation reln)
if (reln == NULL)
reln = smgropen(buf->tag.rnode);
- TRACE_POSTGRESQL_BUFFER_FLUSH_START(reln->smgr_rnode.spcNode,
+ TRACE_POSTGRESQL_BUFFER_FLUSH_START(buf->tag.forkNum,
+ buf->tag.blockNum,
+ reln->smgr_rnode.spcNode,
reln->smgr_rnode.dbNode,
reln->smgr_rnode.relNode);
@@ -1902,7 +1907,9 @@ FlushBuffer(volatile BufferDesc *buf, SMgrRelation reln)
*/
TerminateBufferIO(buf, true, 0);
- TRACE_POSTGRESQL_BUFFER_FLUSH_DONE(reln->smgr_rnode.spcNode,
+ TRACE_POSTGRESQL_BUFFER_FLUSH_DONE(buf->tag.forkNum,
+ buf->tag.blockNum,
+ reln->smgr_rnode.spcNode,
reln->smgr_rnode.dbNode,
reln->smgr_rnode.relNode);
diff --git a/src/backend/utils/probes.d b/src/backend/utils/probes.d
index 18d1b56f5d..65e0b6fe66 100644
--- a/src/backend/utils/probes.d
+++ b/src/backend/utils/probes.d
@@ -3,7 +3,7 @@
*
* Copyright (c) 2006-2009, PostgreSQL Global Development Group
*
- * $PostgreSQL: pgsql/src/backend/utils/probes.d,v 1.7 2009/03/11 23:19:25 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/probes.d,v 1.8 2009/03/22 22:39:05 tgl Exp $
* ----------
*/
@@ -54,10 +54,10 @@ provider postgresql {
probe sort__start(int, bool, int, int, bool);
probe sort__done(bool, long);
- probe buffer__read__start(ForkNumber, BlockNumber, Oid, Oid, Oid, bool);
- probe buffer__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, bool, bool);
- probe buffer__flush__start(Oid, Oid, Oid);
- probe buffer__flush__done(Oid, Oid, Oid);
+ 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__flush__start(ForkNumber, BlockNumber, Oid, Oid, Oid);
+ probe buffer__flush__done(ForkNumber, BlockNumber, Oid, Oid, Oid);
probe buffer__hit(bool);
probe buffer__miss(bool);