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<div>Hello Balazs,</div>
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<div>We found something strange with McKernel when used multiple sockets.</div>
<div>When executing an HPCCG benchmark with openMP threads, it take much more time when threads are in different sockets.</div>
<div>We used numactl to set a cpu mask. (OMP_NUM_THREADS=2 ./mcexec numactl –C 0,2 ~/HPCCG 104 104 104)</div>
<div>For example, using HPCCG with 2 openMP threads, it take around 4.66s with Linux and McKernel using both thread on one socket, and it take 5.42s in McKernel using different sockets when Linux take always 4.66s.</div>
<div>Are you aware of this issue?<br>
Is there a mistake in our execution environment?</div>
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<div>We tried to use the –c parameter of mcexec to set a cpu mask in McKernel application, but it look like it does not have any effect on placement. Is it a deprecated feature or is it not its purpose? </div>
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<div>Thank you in advance for your help.</div>
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<div>Jérémie Finiel</div>
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