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kaushikmitra
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Joined: 11 Apr 2008 Posts: 26 Location: MONTEREY
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If an application is having too much database calla Or if most of the submodules are linked dynamically ,is it the reason for high MIPS value for a Mainframe CPU . How the MIPS value is calculated and what are the general methods of reducing the MIPS value? |
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dick scherrer
Moderator Emeritus
Joined: 23 Nov 2006 Posts: 19244 Location: Inside the Matrix
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Hello kaushikmitra and welcome to the forums,
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How the MIPS value is calculated and what are the general methods of reducing the MIPS |
CPU usage is "calculated" very much the same way an electric or water bill is calculated. It is measured usage. "MIPS value" is not calculated by usage. MIPS value is similar to horsepower in a vehicle. It is a rating of how big a load can be handled.
In order to reduce usage, you must isolate which parts of your application are inefficiently implemented, and implement differently. The way to reduce MIPS value is to purchase a smaller server or remove/disable one or more of the processors used by the system.
One way of the other, i hope the above provides what you wanted. |
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stodolas
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Joined: 13 Jun 2007 Posts: 632 Location: Wisconsin
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Yeah, you never really want to reduce the MIPS on a CPU. Unfortunately people still refer to using too many MIPS and you need to reduce the MIPS this job uses. That is just plain silly when you think about it. That is like saying applicationA uses too many gigahertz on your desktop.
IBM sells their processors based on MIPS but measure program usage using Service Units now. |
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dick scherrer
Moderator Emeritus
Joined: 23 Nov 2006 Posts: 19244 Location: Inside the Matrix
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Hello,
Something i left out before . . .
What decided that this application is using too much cpu? Or database calls or i/o for that matter? For that environment, how is "too much" defined?
Is there a similar application that uses considerably less? Has someone run some type of performance monitor that pointed to this as a potential problem? |
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kaushikmitra
New User
Joined: 11 Apr 2008 Posts: 26 Location: MONTEREY
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Thanks Dick and Stodolas for your reply
So here what I understood - MIPS is the rating of the CPU and does not indicate the CPU usage.
How do then we calculate the annual CPU usage for a mainframe. What my understanding was before that based on the MIPS value ,companies pay the money,i.e. more the MIPS more they have to pay.
What are the factors then that contribute to high Mainframe usage cost ? |
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Craq Giegerich
Senior Member
Joined: 19 May 2007 Posts: 1512 Location: Virginia, USA
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Poor programming, bad jcl, bad system design! |
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kaushikmitra
New User
Joined: 11 Apr 2008 Posts: 26 Location: MONTEREY
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Thanks Crag. But how do poor programming,bad JCL ,bad system design increases the CPU usage . It will be really good help for me if you could provide me with some examples. |
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dick scherrer
Moderator Emeritus
Joined: 23 Nov 2006 Posts: 19244 Location: Inside the Matrix
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Hello,
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What are the factors then that contribute to high Mainframe usage cost ? |
Sometimes, sheer volume contributes to high usage.
As Craig mentioned there are many ways to use more system resources than necessary. Literally everything that can be written, can be written poorly.
For some examples, i'd suggest you search in these forum sections (there is a SEARCH link at the top of the page). There are many examples of performance issues/improvements in the cobol, db2, and other parts of the forum.
If you find something you don't understand, post what you found as well as your question about it. |
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