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  • 1.  how to calculate memory size for an IBMi partition ?

    Posted Fri September 01, 2023 11:46 AM

    Hi All,

    I know the size 32 GB Memory for Power 8 CPU, 64Go for Power9 etc ...

    Why ?

    What is it the rule ?

    Perhaps by CPW ? HTTP Process ? Java Process ?

    Regards,

    Henri Bouvier



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    Henri Bouvier
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  • 2.  RE: how to calculate memory size for an IBMi partition ?

    Posted Fri September 01, 2023 08:29 PM

    Henri

    I would say it's just a rule-of-thumb and nothing more. As of POWER8 core, I personally use 8-16GB per core for low and medium workload. 32GB for heavyweight workload. 



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    Chance favors only the prepared mind.
    -- Louis Pasteur
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    Satid S.
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    Original Message


  • 3.  RE: how to calculate memory size for an IBMi partition ?

    Posted Mon September 04, 2023 02:56 AM

    Hi Satid,

    Thank you for your feedback.
    We estimate the memory size of 5Mo per CPW.
    So I would say it's good practice, but it's not a rule.

    Regards,

    Henri B.



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    Henri Bouvier
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    Original Message


  • 4.  RE: how to calculate memory size for an IBMi partition ?

    Posted Mon September 04, 2023 04:55 AM
      |   view attached

    Hello Henri,

    No matter what you decide to give, depending on the workload it might be sufficient, too much or too little. 

    When running a representative workload, when having Collection Services configured. Looking at the graph "Memory Usage by Pool" will answer this question.

    All you have to do is fire up Navigator for I => Performance => Investigate Data = > Enter the string "Memory" under Perspective.

    I have included a screenshot of this graph to get you going.

    I can only hope this reply was helpful.



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    Rudi Van Helvoirt
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    Original Message


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