Find Batch Requests/sec from SYSPERFINFO

Please start any new threads on our new site at https://forums.sqlteam.com. We've got lots of great SQL Server experts to answer whatever question you can come up with.

All Forums

General SQL Server Forums

Script Library

Find Batch Requests/sec from SYSPERFINFO

Author

Topic

Michael Valentine Jones
Yak DBA Kernel (pronounced Colonel)

7020 Posts

Posted - 2009-01-02 : 18:33:29

I ran into some problems trying to use table master.dbo.sysperfinfo to get the batch requests per second, and posted a question on this thread:
http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=117084

The reply from Mladen let me know that there was a known issue with these counters in SQL 2000 that was documented in this Knowledge Base Article:
BUG: sysperfinfo counters are not time-adjusted
http://support.microsoft.com/kb/555064

The problem is that all time based counters are aggregated values from the point in time that SQL Server starts.

The script below is a workaround that uses two queries with a time delay in between to capture the counter before and after the delay and then calculates the value from the difference divided by the number of seconds.

This script is for Batch Requests/sec, but the same idea could be used for any of the time based counters. By adjusting the @seconds parameter in the script, you can adjust the interval over which the value is calculated.


-- Find_Batch_Requests_Per_Second.sql

declare @cntr_value_1 	numeric(20,3)
declare @cntr_value_2 	numeric(20,3)
declare @seconds	int
declare @delay_time	varchar(12)

-- Set interval in seconds to measure the parameter
set @seconds = 5

-- Set the delay time parameter
set @delay_time = right(convert(varchar(30),dateadd(second,@seconds,0),121),12)

select
	@cntr_value_1 = cntr_value
from
	master.dbo.sysperfinfo
where 
	object_name	= 'SQLServer:SQL Statistics'	AND
	counter_name 	= 'Batch Requests/sec'

-- Wait for @delay_time
waitfor delay @delay_time

select
	@cntr_value_2 = cntr_value
from
	master.dbo.sysperfinfo
where 
	object_name	= 'SQLServer:SQL Statistics'	AND
	counter_name 	= 'Batch Requests/sec'

print	'Compute average Batch Requests/sec over time interval of '+
	convert(varchar(30),@seconds)+' seconds.'
select [Batch Requests/sec] =
	convert(numeric(20,3),round((@cntr_value_2-@cntr_value_1)/@seconds,3))

Results:

Compute average Batch Requests/sec over time interval of 5 seconds.
Batch Requests/sec     
---------------------- 
9.000

(1 row(s) affected)

CODO ERGO SUM

Subscribe to SQLTeam.com

SQLTeam.com Articles via RSS

SQLTeam.com Weblog via RSS

- Advertisement -

Resources