LHC@home

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?

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

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...