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Author robbuckley
Recipients paul.moore, robbuckley, steve.dower, tim.golden, zach.ware
Date 2017-06-06.12:49:39
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os.cpu_count() seems to report incorrect values on windows systems with >64 logical processors

tried it on 2 similar systems, both running windows 7 / 10 with python 3.6.1 64bit (anaconda):

platform1 - 2x Xeon E5-2698v4. 20 cores/CPU = total 80 logical cpus with hyperthreading
platform2 - 2x Xeon E5-2697v3. 14 cores/CPU = total 56 logical cpus with hyperthreading

os.cpu_count() reports 40 cores on platform1 and 56 on platform2

I would expect 80 and 56 respectively. 

I suppose this is because the windows api call used is not aware of processor groups, and reports only the number of processors in the current processor group ( eg GetSystemInfo vs GetMaximumProcessorCount )
Date User Action Args
2017-06-06 12:49:39robbuckleysetrecipients: + robbuckley, paul.moore, tim.golden, zach.ware, steve.dower
2017-06-06 12:49:39robbuckleysetmessageid: <>
2017-06-06 12:49:39robbuckleylinkissue30581 messages
2017-06-06 12:49:39robbuckleycreate