'Finding blocking/locking queries in MS SQL (mssql)

Using sys.dm_os_wait_stats I have identified what I believe is a locking problem

  wait type    waittime  pct     running ptc
  LCK_M_RS_S   2238.54   22.14   22.14
  LCK_M_S      1980.59   19.59   41.73

Is there a way I can find the top blocking/locking queries? I've tried querying sys.dm_db_index_operational_stats without much luck.

sql-serversql-server-2005sql-server-2008query-optimization


Solution 1:[1]

You may find this query useful:

SELECT * 
  FROM sys.dm_exec_requests
  WHERE DB_NAME(database_id) = 'YourDBName' 
    AND blocking_session_id <> 0

To get the query itself use this one:

SELECT text,* 
  FROM sys.dm_exec_requests
  CROSS APPLY sys.dm_exec_sql_text(sql_handle)
  WHERE DB_NAME(database_id) = 'YourDBName' 
    AND blocking_session_id <> 0

Solution 2:[2]

I found this query which helped me find my locked table and query causing the issue.

SELECT  L.request_session_id AS SPID, 
        DB_NAME(L.resource_database_id) AS DatabaseName,
        O.Name AS LockedObjectName, 
        P.object_id AS LockedObjectId, 
        L.resource_type AS LockedResource, 
        L.request_mode AS LockType,
        ST.text AS SqlStatementText,        
        ES.login_name AS LoginName,
        ES.host_name AS HostName,
        TST.is_user_transaction as IsUserTransaction,
        AT.name as TransactionName,
        CN.auth_scheme as AuthenticationMethod
FROM    sys.dm_tran_locks L
        JOIN sys.partitions P ON P.hobt_id = L.resource_associated_entity_id
        JOIN sys.objects O ON O.object_id = P.object_id
        JOIN sys.dm_exec_sessions ES ON ES.session_id = L.request_session_id
        JOIN sys.dm_tran_session_transactions TST ON ES.session_id = TST.session_id
        JOIN sys.dm_tran_active_transactions AT ON TST.transaction_id = AT.transaction_id
        JOIN sys.dm_exec_connections CN ON CN.session_id = ES.session_id
        CROSS APPLY sys.dm_exec_sql_text(CN.most_recent_sql_handle) AS ST
WHERE   resource_database_id = db_id()
ORDER BY L.request_session_id

Solution 3:[3]

Use the script: sp_blocker_pss08 or SQL Trace/Profiler and the Blocked Process Report event class.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 schlebe
Solution 2 ashman786
Solution 3 Martin Smith

Related Questions