Decision Optimization

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Limiting CPU Usage

  • 1.  Limiting CPU Usage

    Posted Thu August 05, 2021 04:27 AM
    Hi,

    I am running my code in ILOG 20.1.0 using CP optimizer. I have an issue s.t. my computer is getting really hot because of 100% CPU usage while running my code. I need to run this code for several days, and I need to limit my CPU usage to 75% or below to cool it. Is there a way to do that?

    Thanks in advance,

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    Ceyhan
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  • 2.  RE: Limiting CPU Usage

    Posted Thu August 05, 2021 07:11 AM

    Hello Muhammet

    By default, the CP solver starts as many workers as the number of CPU cores (including hyper-threading). 

    For long runs, it is preferable to limit the number of workers by setting the "Workers" solver parameters to a lower value, for example 4 that is a good trade-off in general.

    Hope this helps.



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    Olivier Oudot
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  • 3.  RE: Limiting CPU Usage

    Posted Thu August 05, 2021 08:16 AM
    Thank you for the reply Olivier. 

    I am keeping the CPU Time values of solutions. If I limit the number of cores to a lower value than default, does it affect my CPU Time results for the same solution?
    I guess it affects the real time (elapsed time) but I am not sure about CPU Time.


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    Muhammet Ceyhan Şahin
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  • 4.  RE: Limiting CPU Usage

    Posted Fri August 06, 2021 06:32 AM
    Dear Muhammet,

    Assuming you are talking about these time modes https://www.ibm.com/docs/en/icos/20.1.0?topic=parameters-time-mode-parameter. Yes it affects the CPUTime since there are less active workers. If may also change the search result.
    I hope this helps,

                 Renaud

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    Renaud Dumeur
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