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Use of only 25% of CPU with Auto-Parallelization

JB_D_
Beginner
‎04-30-2013 02:12 AM
5,063 Views

Hi,

I'm using Intel Visual Fortran Compiler Pro 11.1 to compile my code on an Intel core i5 architecture.

Because I would like to parallelize the exectution of the programm i use the "-c /Qparallel" option at the compilation step, and the "/Qpar-report" option outputs that almost all the loops have been parrallelized.

But when i execute my programm, only 25% of the total CPU ressource is allocated to the reffering process, enven if all the proccessors seem to work simultaneously. I've tried to set the priority of the process at "/high" when i execute the programm, with no effects, and the affinity is set by default on all the 4 processors.

I don't know what is going wrong, thanks in advance for any help.

JB

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John_Campbell
New Contributor II
‎05-08-2013 08:27 PM
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You indicate your version of ifort Ver 11.1. I have found a significant improvement in /Qparallel changeing to Composer XE 2011, which has been superceeded by Ver 2012 and possibly Ver 2013.
I would recommend you upgrade from Ver 11.1, as I found problems with that version.

John

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