3. 跟踪标记 (Trace Flag) 1204, 1222 抓取死锁信息
跟踪标记:1204/1222
功能及用途:
捕获SQL Server死锁信息,并自动存放到错误日志(ERRORLOG)中。
举例:
USE tempdb GO CREATE TABLE t1(id int) INSERT t1 SELECT 1 CREATE TABLE t2(id int) INSERT t2 SELECT 1 GO --开启1204/1222跟踪标记(任何查询窗口) DBCC TRACEON(1204,-1) --DBCC TRACEON(1205,3605,-1) --DBCC TRACEON(1206,3605,-1) --DBCC TRACEON(1222,-1) GO --查询窗口1 SET LOCK_TIMEOUT -1 SET TRANSACTION ISOLATION LEVEL READ COMMITTED BEGIN TRAN UPDATE t1 SET id = 0 WHERE id=1 WAITFOR DELAY '00:00:05' UPDATE t2 SET id = 0 WHERE id=1 --COMMIT TRAN GO --查询窗口2 SET LOCK_TIMEOUT -1 SET TRANSACTION ISOLATION LEVEL READ COMMITTED --死锁优先级为low,将被选择作为牺牲品 SET DEADLOCK_PRIORITY LOW BEGIN TRAN UPDATE t2 SET id = 0 WHERE id=1 UPDATE t1 SET id = 0 WHERE id=1 --COMMIT TRAN GO --关闭1204/1222跟踪标记(任何查询窗口) DBCC TRACEOFF(1204,-1) --DBCC TRACEOFF(1205,3605,-1) --DBCC TRACEOFF(1206,3605,-1) --DBCC TRACEOFF(1222,-1) GO --查看错误日志里的死锁信息 exec xp_readerrorlog 0,1 DROP TABLE t1,t2
跟踪标记1204 在错误日志中记录的死锁信息
DBCC TRACEON 1204, server process ID (SPID) 56. This is an informational message only; no user action is required. Deadlock encountered .... Printing deadlock information Wait-for graph NULL Node:1 RID: 2:1:624:0 CleanCnt:2 Mode:X Flags: 0x3 Grant List 1: Owner:0x00000034DF20D840 Mode: X Flg:0x40 Ref:0 Life:02000000 SPID:56 ECID:0 XactLockInfo: 0x00000034DDE34440 SPID: 56 ECID: 0 Statement Type: UPDATE Line #: 9 Input Buf: Language Event: --查询窗口1 SET LOCK_TIMEOUT -1 SET TRANSACTION ISOLATION LEVEL READ COMMITTED BEGIN TRAN UPDATE t1 SET id = 0 WHERE id=1 WAITFOR DELAY '00:00:05' UPDATE t2 SET id = 0 WHERE id=1 --COMMIT TRAN Requested by: ResType:LockOwner Stype:'OR'Xdes:0x00000034E122B2B8 Mode: U SPID:58 BatchID:0 ECID:0 TaskProxy:(0x00000034BB418870) Value:0xdf20d040 Cost:(5/224) NULL Node:2 RID: 2:3:944:0 CleanCnt:2 Mode:X Flags: 0x3 Grant List 1: Owner:0x00000034DF20D980 Mode: X Flg:0x40 Ref:0 Life:02000000 SPID:58 ECID:0 XactLockInfo: 0x00000034E122B2F0 SPID: 58 ECID: 0 Statement Type: UPDATE Line #: 8 Input Buf: Language Event: --查询窗口2 SET LOCK_TIMEOUT -1 SET TRANSACTION ISOLATION LEVEL READ COMMITTED SET DEADLOCK_PRIORITY LOW BEGIN TRAN UPDATE t2 SET id = 0 WHERE id=1 UPDATE t1 SET id = 0 WHERE id=1 --COMMIT TRAN Requested by: ResType:LockOwner Stype:'OR'Xdes:0x00000034DDE34408 Mode: U SPID:56 BatchID:0 ECID:0 TaskProxy:(0x00000034BB1DC870) Value:0xdf20ec00 Cost:(0/224) NULL Victim Resource Owner: ResType:LockOwner Stype:'OR'Xdes:0x00000034E122B2B8 Mode: U SPID:58 BatchID:0 ECID:0 TaskProxy:(0x00000034BB418870) Value:0xdf20d040 Cost:(5/224) DBCC TRACEOFF 1204, server process ID (SPID) 56. This is an informational message only; no user action is required.
跟踪标记1222 在错误日志中记录的死锁信息
DBCC TRACEON 1222, server process ID (SPID) 56. This is an informational message only; no user action is required. deadlock-list deadlock victim=process34d71fc4e8 process-list process id=process34d71fc4e8 taskpriority=5 logused=224 waitresource=RID: 2:1:624:0 waittime=3012 ownerId=1281992 transactionname=user_transaction lasttranstarted=2016-10-12T10:11:24.513 XDES=0x34dde34408 lockMode=U schedulerid=2 kpid=5736 status=suspended spid=58 sbid=0 ecid=0 priority=-5 trancount=2 lastbatchstarted=2016-10-12T10:11:24.513 lastbatchcompleted=2016-10-12T10:11:12.760 lastattention=2016-10-12T10:10:46.323 clientapp=Microsoft SQL Server Management Studio - Query hostname=CHRZHANG hostpid=6924 loginname=PCLC0\chrzhang isolationlevel=read committed (2) xactid=1281992 currentdb=2 lockTimeout=4294967295 clientoption1=671090784 clientoption2=390200 executionStack frame procname=adhoc line=9 stmtstart=38 stmtend=116 sqlhandle=0x020000006f1dc606af4ee82be297cae142d4eca1b1b26d840000000000000000000000000000000000000000 unknown frame procname=adhoc line=9 stmtstart=324 stmtend=384 sqlhandle=0x02000000c9c0f33adb0fe790eb6b0e4c7175f9f4b5931a970000000000000000000000000000000000000000 unknown inputbuf --查询窗口2 SET LOCK_TIMEOUT -1 SET TRANSACTION ISOLATION LEVEL READ COMMITTED SET DEADLOCK_PRIORITY LOW BEGIN TRAN UPDATE t2 SET id = 0 WHERE id=1 UPDATE t1 SET id = 0 WHERE id=1 --COMMIT TRAN process id=process34ddc6a4e8 taskpriority=0 logused=224 waitresource=RID: 2:3:944:0 waittime=1071 ownerId=1281979 transactionname=user_transaction lasttranstarted=2016-10-12T10:11:21.440 XDES=0x34e122b2b8 lockMode=U schedulerid=2 kpid=968 status=suspended spid=56 sbid=0 ecid=0 priority=0 trancount=2 lastbatchstarted=2016-10-12T10:11:21.440 lastbatchcompleted=2016-10-12T10:11:04.287 lastattention=1900-01-01T00:00:00.287 clientapp=Microsoft SQL Server Management Studio - Query hostname=CHRZHANG hostpid=6924 loginname=PCLC0\chrzhang isolationlevel=read committed (2) xactid=1281979 currentdb=2 lockTimeout=4294967295 clientoption1=671090784 clientoption2=390200 executionStack frame procname=adhoc line=8 stmtstart=38 stmtend=116 sqlhandle=0x0200000083cd4832d993ca3b2dcaae9f9cc70a25e718dbe90000000000000000000000000000000000000000 unknown frame procname=adhoc line=8 stmtstart=326 stmtend=386 sqlhandle=0x02000000ff6a84274c6888c86c481ae84300231e8f5fb8000000000000000000000000000000000000000000 unknown inputbuf --查询窗口1 SET LOCK_TIMEOUT -1 SET TRANSACTION ISOLATION LEVEL READ COMMITTED BEGIN TRAN UPDATE t1 SET id = 0 WHERE id=1 WAITFOR DELAY '00:00:05' UPDATE t2 SET id = 0 WHERE id=1 --COMMIT TRAN resource-list ridlock fileid=1 pageid=624 dbid=2 objectname=tempdb.dbo.t1 id=lock34d8ea3200 mode=X associatedObjectId=2017612634171244544 owner-list owner id=process34ddc6a4e8 mode=X waiter-list waiter id=process34d71fc4e8 mode=U requestType=wait ridlock fileid=3 pageid=944 dbid=2 objectname=tempdb.dbo.t2 id=lock34d8ea3780 mode=X associatedObjectId=2089670228250132480 owner-list owner id=process34d71fc4e8 mode=X waiter-list waiter id=process34ddc6a4e8 mode=U requestType=wait DBCC TRACEOFF 1222, server process ID (SPID) 56. This is an informational message only; no user action is required.
小结:
(1) 不需要加跟踪标记3605,跟踪标记1204,1222捕获的死锁信息便会被写到错误日志;
(2) 跟踪标记 1222以XML样式返回死锁信息,相比跟踪标记1204,返回的信息也更为丰富;
(3) 无文档记载的跟踪标记1205,1206,据说可以用来丰富1204捕获死锁的信息,在SQL Server 2016下简单测试同时开启1204,1205,1206,和单独开启1204并没发现有什么不同,个人猜测是随着版本更替,跟踪标记捕获的死锁信息已经被整合,直接用1204或1222即可;
(4) 从SQL Server 2008开始,引进了扩展事件(Extended Events),也可以用来捕获死锁信息。
参考:
Tracing a SQL Server Deadlock
https://www.mssqltips.com/sqlservertutorial/252/tracing-a-sql-server-deadlock/
Trace Flags - SQL Server Wiki - SQL Server - Toad World
https://www.toadworld.com/platforms/sql-server/w/wiki/9790.trace-flags
Using SQL Server 2008 Extended Events
https://technet.microsoft.com/en-us/library/dd822788%28v=sql.100%29.aspx?f=255&MSPPError=-2147217396