SQL SERVER – Wait Stats Collection Scripts : Updated March 2021

SQL Wait Statistics is my favorite topic. The very first script which I sent to my clients during Comprehensive Database Performance Health Check is SQL Wait Statistics. I have recently updated my SQL Wait Stats Collection Script for my clients. In today’s blog post we will be looking at the newly updated SQL Wait Statistics Script.

Once you run the following script, you can find a list of the resource bottlenecks in your system.

-- ------------------------------------------------------
-- Tip: Wait Statistics
-- (c) https://blog.sqlauthority.com/
-- Additional resources - http://bit.ly/WaitStats
-- ------------------------------------------------------
/*
-- Script to Clear Wait Types
DBCC SQLPERF('sys.dm_os_wait_stats', CLEAR);
GO
*/
--http://go.sqlauthority.com
-- SQL Wait Stats and Queries
-- (C) Pinal Dave https://blog.sqlauthority.com/) 2021+
-- Send query result to pinal@sqlauthority.com for quick feedback
SELECT wait_type AS Wait_Type,
wait_time_ms / 1000.0 AS Wait_Time_Seconds,
waiting_tasks_count AS Waiting_Tasks_Count,
-- CAST((wait_time_ms / 1000.0)/waiting_tasks_count AS decimal(10,4)) AS AVG_Waiting_Tasks_Count,
wait_time_ms * 100.0 / SUM(wait_time_ms) OVER() AS Percentage_WaitTime
--,waiting_tasks_count * 100.0 / SUM(waiting_tasks_count) OVER() AS Percentage_Count
FROM sys.dm_os_wait_stats
WHERE wait_type NOT IN
(N'BROKER_EVENTHANDLER',
N'BROKER_RECEIVE_WAITFOR',
N'BROKER_TASK_STOP',
N'BROKER_TO_FLUSH',
N'BROKER_TRANSMITTER',
N'CHECKPOINT_QUEUE',
N'CHKPT',
N'CLR_AUTO_EVENT',
N'CLR_MANUAL_EVENT',
N'CLR_SEMAPHORE',
N'CXCONSUMER',
N'DBMIRROR_DBM_EVENT',
N'DBMIRROR_DBM_MUTEX',
N'DBMIRROR_EVENTS_QUEUE',
N'DBMIRROR_WORKER_QUEUE',
N'DBMIRRORING_CMD',
N'DIRTY_PAGE_POLL',
N'DISPATCHER_QUEUE_SEMAPHORE',
N'EXECSYNC',
N'FSAGENT',
N'FT_IFTS_SCHEDULER_IDLE_WAIT',
N'FT_IFTSHC_MUTEX',
N'HADR_CLUSAPI_CALL',
N'HADR_FILESTREAM_IOMGR_IOCOMPLETION',
N'HADR_LOGCAPTURE_WAIT',
N'HADR_NOTIFICATION_DEQUEUE',
N'HADR_TIMER_TASK',
N'HADR_WORK_QUEUE',
N'LAZYWRITER_SLEEP',
N'LOGMGR_QUEUE',
N'MEMORY_ALLOCATION_EXT',
N'ONDEMAND_TASK_QUEUE',
N'PARALLEL_REDO_DRAIN_WORKER',
N'PARALLEL_REDO_LOG_CACHE',
N'PARALLEL_REDO_TRAN_LIST',
N'PARALLEL_REDO_WORKER_SYNC',
N'PARALLEL_REDO_WORKER_WAIT_WORK',
N'PREEMPTIVE_HADR_LEASE_MECHANISM',
N'PREEMPTIVE_OS_FLUSHFILEBUFFERS',
N'PREEMPTIVE_OS_AUTHENTICATIONOPS',
N'PREEMPTIVE_OS_AUTHORIZATIONOPS',
N'PREEMPTIVE_OS_COMOPS',
N'PREEMPTIVE_OS_CREATEFILE',
N'PREEMPTIVE_OS_CRYPTOPS',
N'PREEMPTIVE_OS_DEVICEOPS',
N'PREEMPTIVE_OS_FILEOPS',
N'PREEMPTIVE_OS_GENERICOPS',
N'PREEMPTIVE_OS_LIBRARYOPS',
N'PREEMPTIVE_OS_PIPEOPS',
N'PREEMPTIVE_OS_QUERYREGISTRY',
N'PREEMPTIVE_OS_VERIFYTRUST',
N'PREEMPTIVE_OS_WAITFORSINGLEOBJECT',
N'PREEMPTIVE_OS_WRITEFILEGATHER',
N'PREEMPTIVE_SP_SERVER_DIAGNOSTICS',
N'PREEMPTIVE_XE_CALLBACKEXECUTE',
N'PREEMPTIVE_XE_DISPATCHER',
N'PREEMPTIVE_XE_GETTARGETSTATE',
N'PREEMPTIVE_XE_SESSIONCOMMIT',
N'PREEMPTIVE_XE_TARGETFINALIZE',
N'PREEMPTIVE_XE_TARGETINIT',
N'PWAIT_ALL_COMPONENTS_INITIALIZED',
N'PWAIT_EXTENSIBILITY_CLEANUP_TASK',
N'PWAIT_DIRECTLOGCONSUMER_GETNEXT',
N'QDS_ASYNC_QUEUE',
N'QDS_CLEANUP_STALE_QUERIES_TASK_MAIN_LOOP_SLEEP',
N'QDS_PERSIST_TASK_MAIN_LOOP_SLEEP',
N'QDS_SHUTDOWN_QUEUE',
N'REDO_THREAD_PENDING_WORK',
N'REQUEST_FOR_DEADLOCK_SEARCH',
N'RESOURCE_QUEUE',
N'SERVER_IDLE_CHECK',
N'SOS_WORK_DISPATCHER',
N'SLEEP_BPOOL_FLUSH',
N'SLEEP_DBSTARTUP',
N'SLEEP_DCOMSTARTUP',
N'SLEEP_MASTERDBREADY',
N'SLEEP_MASTERMDREADY',
N'SLEEP_MASTERUPGRADED',
N'SLEEP_MSDBSTARTUP',
N'SLEEP_SYSTEMTASK',
N'SLEEP_TASK',
N'SLEEP_TEMPDBSTARTUP',
N'SNI_HTTP_ACCEPT',
N'SP_SERVER_DIAGNOSTICS_SLEEP',
N'SQLTRACE_BUFFER_FLUSH',
N'SQLTRACE_INCREMENTAL_FLUSH_SLEEP',
N'SQLTRACE_WAIT_ENTRIES',
N'STARTUP_DEPENDENCY_MANAGER',
N'UCS_SESSION_REGISTRATION',
N'VDI_CLIENT_OTHER',
N'WAIT_FOR_RESULTS',
N'WAIT_XTP_CKPT_CLOSE',
N'WAIT_XTP_HOST_WAIT',
N'WAIT_XTP_OFFLINE_CKPT_NEW_LOG',
N'WAIT_XTP_RECOVERY',
N'WAITFOR',
N'WAITFOR_TASKSHUTDOWN',
N'XE_BUFFERMGR_ALLPROCESSED_EVENT',
N'XE_DISPATCHER_JOIN',
N'XE_TIMER_EVENT',
N'XE_DISPATCHER_WAIT',
N'XE_LIVE_TARGET_TVF'
) AND wait_time_ms > 1
ORDER BY Wait_Time_Seconds DESC
-- ORDER BY Waiting_Tasks_Count DESC

Here is the list of all the resources you may need to resolve any issue with SQL Wait Stats. Make sure that you bookmark this page as it contains links to valuable resources.

• SQL SERVER – Wait Stats – Wait Types – Wait Queues – Day 0 of 28
• Get Wait Stats Related to Specific Session ID With sys.dm_exec_session_wait_stats
• Wait Statistics from Query Execution Plan
• Query Specific Wait Statistics and Performance Tuning
• Detecting CPU Pressure with Wait Statistics

Alternatively, you can also send your SQL Wait Stats to me (via email pinal@sqlauthority.com) in an excel file and I will take a look at that and will give you my quick feedback about your resource bottleneck. I am confident that you will find Wait Stats Collection Scripts helpful. You can also subscribe to my YouTube Video.

Reference: Pinal Dave (https://blog.sqlauthority.com)