Re: Question on effectiveness of additional processors -- MIDRANGE-L

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Dawn

On Sep 28, 2022, at 1:09 PM, MidrangeL <midrangel@xxxxxxxxxxxxxxxxx> wrote:

That answer is: "it depends"

Is the system processor constrained? IE: is the CPU % at or near 90% during peak times? Is there latent demand that is only met after a period of waiting?
Is the system memory constrained? Are paging and faulting levels high enough that the system spends quite a bit of resource moving memory around?
Is the system I/O constrained? Is the system waiting for I/O operations to complete before moving on to the next task? Look at Disk busy during peak loads.

Each of those questions can be answered by the performance tools, which will then guide you where to spend your money. Adding a core will most likely improve system responsiveness either way since I/O and Memory also include using system resources to maximize them, but that may not be the root cause of the performance issue.

Check out Dawn May's blogs regarding using the performance tools to diagnose the problem. Then you will spend the correct money on the correct thing. Don't know how to use the tools; get your business partner or an independent consultant to look at it. IBM will do it as well via the Lab Services Group.

--
Jim Oberholtzer
Chief Technical Architect
Agile Technology Architects

------ Original Message ------
From "a4g atl" <a4ginatl2@xxxxxxxxx>
To "midrange-l@xxxxxxxxxxxxxxxxxx" <midrange-l@xxxxxxxxxxxxxxxxxx>
Date 9/28/2022 11:57:12 AM
Subject Question on effectiveness of additional processors

How effective are additional processors on the system.

We have a Power8 with 1 processor activated.
If we activate another processor or 2, what benefits should I see?
I have heard that the additional processor will not make much difference,
so why would IBM provide for additional processors?

What am I missing?

TIA, Darryl Freinkel.
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