Satish5
New User
Joined: 12 Nov 2007
Posts: 38
Location: Texas, USA
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I was asked how to optimize DB2 from programmers point of view. If a DB2/COBOL prog is takin 5 hours then how the execution time can be reduced to say 40 mins.
I have seen large complex confusing manuals, but can some one please share optimization techniqueus in simple form.
Thansk,
Satish |
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Robert Sample
Global Moderator
Joined: 06 Jun 2008
Posts: 8697
Location: Dubuque, Iowa, USA
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| Quote: |
| If a DB2/COBOL prog is takin 5 hours then how the execution time can be reduced to say 40 mins. |
How do you know this goal can be achieved, even?
First, you have to find out if the job is CPU-bound or I/O-bound. For CPU-bound jobs, find out what is taking all the CPU time and minimize it (which may reduce the run time but may not). For I/O-bound jobs, you can work with your site storage team to reduce channel and disk contention, but this again may or may not reduce run time.
Bottom line: there are no guaranteed, 100% effective all-the-time methods to reduce run time. If the run time has already been reduced to the minimum, then short of buying a faster machine with faster disk drives there may no way to reduce the run time. |
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