利用扩展事件(Xevents)捕捉高消耗查询

生产环境中有时需要使用者抓取一些特定的语句分析,如超超长查询,或高IO查询等.一般来说大家对跟踪比较熟悉,主要因为其有完善的UI支持.由于扩展事件在sql2012才提供UI支持,所以虽然在08时就已经存在的更轻量级的扩展事件没有被广泛使用.这里和大家分享一个扩展事件脚本,用来捕捉高消耗的查询语句.

注意:使用完毕后应停止扩展事件捕捉.

应根据自身实际需求设置过滤条件,如CPU,duration,Reads等

在sql2012中会提供更为丰富的内容(如query_hash等)

code 1 将扩展事件追踪保存到本地文件中

CREATE EVENT session L_QUERIES ON SERVER ADD EVENT sqlserver.sql_statement_completed(    ACTION(sqlserver.username,sqlserver.client_hostname,sqlserver.database_id,sqlserver.session_id,sqlserver.sql_text,sqlserver.plan_handle)    WHERE (cpu>1000 AND duration>=5000000 and Reads>=10000 and sqlserver.database_id=17)) ADD TARGET package0.asynchronous_file_target   (SET FILENAME = N'D:/L_QUERIES.xel', METADATAFILE = N'D:/L_QUERIES.xem')WITH (max_dispatch_latency = 1 seconds);--cpu 1s--duration 5s--reads io 10000--database_id 17 if you do not need it ,cut outGOALTER EVENT SESSION L_QUERIES ON SERVER STATE = START;------start the eventGO SELECT   data.value (      '(/event[@name=''sql_statement_completed'']/@timestamp)[1]', 'DATETIME') AS [Time],   data.value (      '(/event/data[@name=''cpu'']/value)[1]', 'INT') AS [CPU (ms)],   data.value (      '(/event/data[@name=''reads'']/value)[1]', 'BIGINT') AS [Reads],      data.value (      '(/event/action[@name=''session_id'']/value)[1]', 'smallint') AS [session_id],      data.value (      '(/event/action[@name=''database_id'']/value)[1]', 'smallint') AS [database_id],   CONVERT (FLOAT, data.value ('(/event/data[@name=''duration'']/value)[1]', 'BIGINT')) / 1000000      AS [Duration (s)],   data.value (        '(/event/action[@name=''username'']/value)[1]', 'VARCHAR(100)') AS [username],   data.value  (           '(/event/action[@name=''client_hostname'']/value)[1]', 'VARCHAR(100)') AS [client_hostname],   data.value  (              '(/event/action[@name=''sql_text'']/value)[1]', 'VARCHAR(MAX)') AS [SQL Statement],   SUBSTRING (data.value ('(/event/action[@name=''plan_handle'']/value)[1]', 'VARCHAR(100)'), 15, 50)      AS [Plan Handle]FROM   (SELECT CONVERT (xml, event_data) AS data FROM sys.fn_xe_file_target_read_file      ('D:/L_QUERIES*.xel', 'D:/L_QUERIES*.xem', null, null)) entriesORDER BY [Time] DESC;----------query the event info what you need--ALTER EVENT SESSION L_QUERIES ON SERVER STATE = STOP;---stop the event--DROP EVENT SESSION L_QUERIES ON SERVER;------------drop the event

code2 将扩展事件保存到ring buffer中

CREATE EVENT SESSION L_QUERIES ON SERVER ADD EVENT sqlserver.sql_statement_completed(    ACTION(sqlserver.username,sqlserver.client_hostname,sqlserver.database_id,sqlserver.session_id,sqlserver.sql_text,sqlserver.plan_handle)    WHERE (cpu>1000 AND duration>=5000000 and Reads>=10000 and sqlserver.database_id=17))     ADD TARGET package0.ring_buffer        (SET max_memory = 4000) -----not the default 4096kb   WITH (max_dispatch_latency = 1 seconds) --cpu 1s--duration 5s--reads io 10000--database_id 17 if you do not need it ,cut outGOALTER EVENT SESSION L_QUERIES ON SERVER STATE = START;------start the eventGO DECLARE @target_data XMLSELECT  @target_data=CAST(target_data AS XML)FROM sys.dm_xe_sessions AS s JOIN sys.dm_xe_session_targets AS t     ON t.event_session_address = s.addressWHERE s.name = 'L_QUERIES'  AND t.target_name = 'ring_buffer'   SELECT   t.value('(@timestamp)[1]', 'datetime2') AS [time],   t.value ('(data[@name=''cpu'']/value)[1]', 'INT') AS [CPU (ms)],   t.value ('(data[@name=''reads'']/value)[1]', 'BIGINT') AS [Reads],      t.value ('(action[@name=''session_id'']/value)[1]', 'smallint') AS [session_id],      t.value ('(action[@name=''database_id'']/value)[1]', 'smallint') AS [database_id],   CONVERT (FLOAT, t.value ('(data[@name=''duration'']/value)[1]', 'BIGINT')) / 1000000      AS [Duration (s)],   t.value ('(action[@name=''username'']/value)[1]', 'VARCHAR(100)') AS [username],   t.value ('(action[@name=''client_hostname'']/value)[1]', 'VARCHAR(100)') AS [client_hostname],   t.value ('(action[@name=''sql_text'']/value)[1]', 'VARCHAR(MAX)') AS [SQL Statement],   SUBSTRING (t.value ('(action[@name=''plan_handle'']/value)[1]', 'VARCHAR(100)'), 15, 50)      AS [Plan Handle]    FROM @target_data.nodes('RingBufferTarget/event') AS q(t)ORDER BY [Time] DESC;----------query the event info what you need--ALTER EVENT SESSION L_QUERIES ON SERVER STATE = STOP;---stop the event--DROP EVENT SESSION L_QUERIES ON SERVER-----------drop the event