From: Date: August 27 2008 7:03pm
Subject: RE: bzr commit into mysql-6.0-falcon branch (cpowers:2801) Bug#38566
List-Archive: http://lists.mysql.com/commits/52763
Message-Id: <007301c90866$e764a930$b62dfb90$@com>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: 7bit

OK to push

>-----Original Message-----
>From: Christopher Powers [mailto:cpowers@stripped]
>Sent: Wednesday, August 27, 2008 2:09 AM
>To: commits@stripped
>Subject: bzr commit into mysql-6.0-falcon branch (cpowers:2801) Bug#38566
>
>#At file:///home/cpowers/work/dev/dev-06/mysql/
>
> 2801 Christopher Powers	2008-08-27
>      Bug #38566 Falcon crash in RecordVersion::thaw at
>RecordVersion.cpp:421
>
>      Removed unnecessary log messages
>      Modified assertions to accommodate race condition where two threads
>thaw the same record
>modified:
>  storage/falcon/RecordVersion.cpp
>  storage/falcon/SRLUpdateRecords.cpp
>
>per-file messages:
>  storage/falcon/RecordVersion.cpp
>    RecordVersion::thaw()
>    - Removed unnecessary log debug messages
>    - Check record state before asserting on number of bytes restored
>  storage/falcon/SRLUpdateRecords.cpp
>    SRLUpdateRecords::thaw()
>    - Only assert on record number if record was actually thawed
>    - Update chill/thaw byte counts if record was actualy thawed
>    - setRecordData() checks for race condition using compare and exchange
>pointer, so no need to assert if record wasn't thawed by current thread
>=== modified file 'storage/falcon/RecordVersion.cpp'
>--- a/storage/falcon/RecordVersion.cpp	2008-07-15 18:57:27 +0000
>+++ b/storage/falcon/RecordVersion.cpp	2008-08-27 07:08:18 +0000
>@@ -416,11 +416,9 @@ int RecordVersion::thaw()
> 			}
> 		}
>
>-	if (bytesRestored <= 0)
>-		Log::debug("RecordVersion::thaw: writePending %d, was %d,
>recordFetched %d, data %p\n",
>-					trans->writePending,
wasWritePending,
>recordFetched, data.record);
>-
>-	ASSERT(bytesRestored > 0 || data.record == NULL);
>+	if (state == recChilled)
>+		ASSERT(bytesRestored > 0 || data.record == NULL);
>+
> 	state = recData;
>
> 	return bytesRestored;
>
>=== modified file 'storage/falcon/SRLUpdateRecords.cpp'
>--- a/storage/falcon/SRLUpdateRecords.cpp	2008-04-09 08:23:51 +0000
>+++ b/storage/falcon/SRLUpdateRecords.cpp	2008-08-27 07:08:18 +0000
>@@ -84,34 +84,39 @@ int SRLUpdateRecords::thaw(RecordVersion
> 	// Get section id, record id and data length written. Input pointer
>will be at
> 	// beginning of record data.
>
>-	int tableSpaceId;
>+	int tableSpaceId = 0;
>
> 	if (control->version >= srlVersion8)
> 		tableSpaceId = control->getInt();
>-	else
>-		tableSpaceId = 0;
>
> 	control->getInt();			// sectionId
> 	int recordNumber = control->getInt();
> 	int dataLength   = control->getInt();
>-	ASSERT(recordNumber == record->recordNumber);
>-	int bytesReallocated = record->setRecordData(control->input,
>dataLength);
>+	int bytesReallocated = 0;
>+
>+	// setRecordData() handles race conditions with an interlocked
compare
>and exchange,
>+	// but check the state and record number anyway
>
>-	if (bytesReallocated > 0)
>-		bytesReallocated = record->getEncodedSize();
>+	if (record->state == recChilled && recordNumber == record-
>>recordNumber)
>+		bytesReallocated = record->setRecordData(control->input,
>dataLength);
>
> 	window->deactivateWindow();
>
>-	if (log->chilledRecords > 0)
>-		log->chilledRecords--;
>+	if (bytesReallocated > 0)
>+		{
>+		ASSERT(recordNumber == record->recordNumber);
>+		bytesReallocated = record->getEncodedSize();
>+		*thawed = true;
>+
>+		if (log->chilledRecords > 0)
>+			log->chilledRecords--;
>
>-	if (log->chilledBytes > uint64(bytesReallocated))
>-		log->chilledBytes -= bytesReallocated;
>-	else
>-		log->chilledBytes = 0;
>-
>-	*thawed = true;
>-
>+		if (log->chilledBytes > uint64(bytesReallocated))
>+			log->chilledBytes -= bytesReallocated;
>+		else
>+			log->chilledBytes = 0;
>+		}
>+
> 	return bytesReallocated;
> }
>
>
>
>--
>MySQL Code Commits Mailing List
>For list archives: http://lists.mysql.com/commits
>To unsubscribe:    http://lists.mysql.com/commits?unsub=klewis@stripped