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SQL Server-väntehändelser -1

Hej,

Du bör hitta vilka av väntande händelser som finns i SQL Server-databasen.

För att lösa långsamheten i SQL Server-databasen bör du hitta vilka väntehändelser som finns i databasen.

Du kan hitta väntande händelser i databasen med följande fråga.

with waits as
(select
wait_type,
wait_time_ms / 1000.0 as waits,
(wait_time_ms - signal_wait_time_ms) / 1000.0 as resources,
signal_wait_time_ms / 1000.0 as signals,
waiting_tasks_count as waitcount,
100.0 * wait_time_ms / sum (wait_time_ms) over() as percentage,
row_number() over(order by wait_time_ms desc) as rownum
from sys.dm_os_wait_stats
where wait_type not in (
N'CLR_SEMAPHORE', N'LAZYWRITER_SLEEP',
N'RESOURCE_QUEUE', N'SQLTRACE_BUFFER_FLUSH',
N'SLEEP_TASK', N'SLEEP_SYSTEMTASK',
N'WAITFOR', N'HADR_FILESTREAM_IOMGR_IOCOMPLETION',
N'CHECKPOINT_QUEUE', N'REQUEST_FOR_DEADLOCK_SEARCH',
N'XE_TIMER_EVENT', N'XE_DISPATCHER_JOIN',
N'LOGMGR_QUEUE', N'FT_IFTS_SCHEDULER_IDLE_WAIT',
N'BROKER_TASK_STOP', N'CLR_MANUAL_EVENT',
N'CLR_AUTO_EVENT', N'DISPATCHER_QUEUE_SEMAPHORE',
N'TRACEWRITE', N'XE_DISPATCHER_WAIT',
N'BROKER_TO_FLUSH', N'BROKER_EVENTHANDLER',
N'FT_IFTSHC_MUTEX', N'SQLTRACE_INCREMENTAL_FLUSH_SLEEP',
N'DIRTY_PAGE_POLL', N'SP_SERVER_DIAGNOSTICS_SLEEP')
)
select
w1.wait_type as waittype, 
cast (w1.waits as decimal(14, 2)) wait_s,
cast (w1.resources as decimal(14, 2)) resource_s,
cast (w1.signals as decimal(14, 2)) signal_s,
w1.waitcount wait_count,
cast (w1.percentage as decimal(4, 2)) percentage,
cast ((w1.waits / w1.waitcount) as decimal (14, 4)) avgWait_s,
cast ((w1.resources / w1.waitcount) as decimal (14, 4)) avgResource_s,
cast ((w1.signals / w1.waitcount) as decimal (14, 4)) avgSignal_s
from waits as w1
inner join waits as w2 on w2.rownum <= w1.rownum
group by w1.rownum, w1.wait_type, w1.waits, w1.resources, w1.signals, w1.waitcount, w1.percentage
having sum (w2.percentage) - w1.percentage < 95; -- percentage threshold


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