Message boards : ATLAS application : A very strange situation
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NOGOOD

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Message 39011 - Posted: 31 May 2019, 17:08:30 UTC

Hello.

I discovered a very strange situation... If I run 4-core ATLAS tasks, I can get only 4 tasks... If I run 3-core ATLAS tasks, I can get only 3 tasks... If I run 2-core ATLAS tasks, I can get only 2 tasks... Why so? How can I run, for example, 12 2-core ATLAS tasks at 24-core PC to run tasks most effectively?
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computezrmle
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Message 39012 - Posted: 31 May 2019, 17:43:36 UTC - in response to Message 39011.  

David Cameron explained the reason for this unusual behavior more than a year ago:
https://lhcathome.cern.ch/lhcathome/forum_thread.php?id=4686&postid=35267
I guess only the accountants he mentioned will ever agree that this "feature" of the ATLAS setup is not nonsense.

You may work around this by setting your "Max # CPUs" to unlimited or at least a higher number than necessary.
Be aware that this will also influence the value of <rsc_memory_bound> which is calculated at the server based on the #CPUs.
If your computers have not much RAM this could be a limiting factor.

Unlike that the values for <avg_ncpus> and "memory_size_mb" can be adjusted to your needs using an app_config.xml
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NOGOOD

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Message 39015 - Posted: 31 May 2019, 21:47:35 UTC - in response to Message 39012.  

David Cameron explained the reason for this unusual behavior more than a year ago:
https://lhcathome.cern.ch/lhcathome/forum_thread.php?id=4686&postid=35267
I guess only the accountants he mentioned will ever agree that this "feature" of the ATLAS setup is not nonsense.

You may work around this by setting your "Max # CPUs" to unlimited or at least a higher number than necessary.
Be aware that this will also influence the value of <rsc_memory_bound> which is calculated at the server based on the #CPUs.
If your computers have not much RAM this could be a limiting factor.

Unlike that the values for <avg_ncpus> and "memory_size_mb" can be adjusted to your needs using an app_config.xml

Actually... Crazy accuracy...
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Message boards : ATLAS application : A very strange situation


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