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How we can reduce the CPU runtime for a job?

 
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sivasu_usavis

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PostPosted: Mon Jan 07, 2008 3:03 pm    Post subject: How we can reduce the CPU runtime for a job?
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Hi All,

I'm facing a difficult issue. Its all about performance of the program. Is there any way possible to reduce the CPU run time of the Job which is executing a IMS program?

Previously It was running with minimum CPU time. Now it got increased. Its a IMS program, It itself calling a sub program as it was executing earlier.

Can you tell me, the possibilities which causes this situation?
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Aaru

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PostPosted: Mon Jan 07, 2008 3:33 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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sivasu,

Quote:
It was running with minimum CPU time. Now it got increased


What changes did u make? Adding functionalities will definitely increase the CPU time.
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sivasu_usavis

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PostPosted: Mon Jan 07, 2008 3:46 pm    Post subject:
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We didnt add any more functionalities on existing program.
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enrico-sorichetti

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PostPosted: Mon Jan 07, 2008 3:51 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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What makes You think that You have a problem??

Higher CPU consumption is not a symptom of something going wrong...
maybe simply there is more work to do

something has certainly changed in Your "environment"
it' s Your job to find out what!

we certainly cannot tell from here
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sivasu_usavis

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PostPosted: Mon Jan 07, 2008 4:05 pm    Post subject:
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I understand your reply e-s. I would say 'environment' change is one of the possibility to cause this. Friend E-S Can you bit elabrate What exactly you meant the 'Environment' Change.

I'm not sure, whether size of the data causes this issue? Any other, possibilities?
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enrico-sorichetti

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PostPosted: Mon Jan 07, 2008 4:10 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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More work to do means more resources used !
what about the elapsed time ?
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sivasu_usavis

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PostPosted: Mon Jan 07, 2008 4:16 pm    Post subject:
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Total elapsed time is all about 2 hrs and 20 ins. But CPU time is 18 mins.
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enrico-sorichetti

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PostPosted: Mon Jan 07, 2008 4:18 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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Quote:
Total elapsed time is all about 2 hrs and 20 ins. But CPU time is 18 mins.


Ok as an absolute measurement,
You complained about cpu usage being higher than before,
what was the elapsed before??
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sivasu_usavis

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PostPosted: Mon Jan 07, 2008 5:44 pm    Post subject:
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Before it was all abt 10 mins. elasped time is abt 30 mins
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enrico-sorichetti

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PostPosted: Mon Jan 07, 2008 5:47 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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Please stop complaining,
assuming a steady state work flow increment
there is absolutely nothing wrong whit those numbers

What made You think about having a problem

again..
how many records were processed before
and how many after ???
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sivasu_usavis

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PostPosted: Mon Jan 07, 2008 6:05 pm    Post subject:
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My compliant is like, whether it was caused by any kind insufficient buffer size or like that? I expecting suggestions, which may cause this. Not expecting any kind of ready made ans, ma fren e-s.
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enrico-sorichetti

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PostPosted: Mon Jan 07, 2008 6:09 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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again i ask how may record were processed before and how many after
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enrico-sorichetti

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PostPosted: Mon Jan 07, 2008 6:17 pm    Post subject: Reply to: How we can reduce the CPU runtime for a job?
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but...
You are looking at the wrong side of things,
I would be much more worried about the elapsed rather than the CPU

the elapsed is almost five time, the cpu did not even double

meditate please and come up with more meaningful information

again in a changing environment
elaps(30) cpu(10)
elaps(150) cpu(18)
are more than normal ,

also remember, that due to buffering and access mode the resource consumption growth
might not be linear
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