Solved

dbcc sqlperf (waitstats) how to evaluate this info when it comes to performance issue?

Posted on 2007-11-25
1
332 Views
Last Modified: 2012-05-05
I would like to know when it comes to performance issue, how do I take the info return from this table to pintpoint the problem,  dbcc sqlperf (waitstats) will show us the wait statistics but I dunno how to use the data from this dbcc commands to relate with the performance that I encounter
0
Comment
Question by:motioneye
1 Comment
 
LVL 31

Accepted Solution

by:
James Murrell earned 500 total points
ID: 20346306
taken this from -http://www.sqldev.net/articles/dbcc_sqlperf_waitstats.htm

DBCC SQLPERF(WAITSTATS) reports two wait times: [Wait Time] and [Signal Wait Time]

[Wait Time] is the total wait time between the time that the worker starts waiting on the resource (T0) and the time the workers gets scheduled in (T2).

[Signal Wait Time] is the time between the time that the worker got signaled (T1) that the resource is available and the time it got scheduled in (T2)

This means that you need to calculate the wait time on the resource by substracting [Wait Time] from [Signal Wait Time].

Note: For more information on UMS see Inside the SQL Server 2000 User Mode Scheduler

The table structure returned, has the following shape:

create table #waitstats
(
    [Wait Type]        nvarchar(32) not null,
    [Requests]         float not null,
    [Wait Time]        float not null,
    [Signal Wait Time] float not null
)

To populate the table use:

insert into #waitstats exec('dbcc sqlperf(waitstats) with tableresults, no_infomsgs')
select * from #waitstats

DBCC SQLPERF(WAITSTATS, CLEAR) resets the counters, this is a service/instance wide reset, not per session!

NOTE: For SQL Server 2005, please use the sys.dm_os_wait_stats dynamic management view instead of DBCC SQLPERF(waitstats), also the sys.dm_os_waiting_tasks table provides information on all currently waiting tasks in the system.
0

Featured Post

Announcing the Most Valuable Experts of 2016

MVEs are more concerned with the satisfaction of those they help than with the considerable points they can earn. They are the types of people you feel privileged to call colleagues. Join us in honoring this amazing group of Experts.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Nowadays, some of developer are too much worried about data. Who is using data, who is updating it etc. etc. Because, data is more costlier in term of money and information. So security of data is focusing concern in days. Lets' understand the Au…
When you hear the word proxy, you may become apprehensive. This article will help you to understand Proxy and when it is useful. Let's talk Proxy for SQL Server. (Not in terms of Internet access.) Typically, you'll run into this type of problem w…
Using examples as well as descriptions, and references to Books Online, show the different Recovery Models available in SQL Server and explain, as well as show how full, differential and transaction log backups are performed
Viewers will learn how the fundamental information of how to create a table.

856 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question