-- Isolate top waits for server instance since last restart or statistics clearWITH Waits AS(SELECT wait_type, wait_time_ms / 1000. AS wait_time_s,100. * wait_time_ms / SUM(wait_time_ms) OVER() AS pct,ROW_NUMBER() OVER(ORDER BY wait_time_ms DESC) AS rnFROM sys.dm_os_wait_statsWHERE wait_type NOT IN('CLR_SEMAPHORE','LAZYWRITER_SLEEP','RESOURCE_QUEUE','SLEEP_TASK','SLEEP_SYSTEMTASK','SQLTRACE_BUFFER_FLUSH','WAITFOR','LOGMGR_QUEUE','CHECKPOINT_QUEUE','REQUEST_FOR_DEADLOCK_SEARCH','XE_TIMER_EVENT','BROKER_TO_FLUSH','BROKER_TASK_STOP','CLR_MANUAL_EVENT','CLR_AUTO_EVENT','DISPATCHER_QUEUE_SEMAPHORE','FT_IFTS_SCHEDULER_IDLE_WAIT','XE_DISPATCHER_WAIT', 'XE_DISPATCHER_JOIN','SQLTRACE_INCREMENTAL_FLUSH_SLEEP'))SELECT W1.wait_type,CAST(W1.wait_time_s AS DECIMAL(12, 2)) AS wait_time_s,CAST(W1.pct AS DECIMAL(12, 2)) AS pct,CAST(SUM(W2.pct) AS DECIMAL(12, 2)) AS running_pctFROM Waits AS W1INNER JOIN Waits AS W2ON W2.rn <= W1.rnGROUP BY W1.rn, W1.wait_type, W1.wait_time_s, W1.pctHAVING SUM(W2.pct) - W1.pct < 99 OPTION (RECOMPILE); -- percentage thresholdGO
This dynamic management view collects all the information since the time when the SQL Server services have been restarted. You can also manually clear the wait stats using t
