CPU Usage (again)

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
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Prosperent
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Joined: 2011-09-29T10:01:56-07:00
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CPU Usage (again)

Post by Prosperent »

We recently upgraded our cluster to centos 6, and seem to be having cpu usage problems with imagemagick once again. I have edited the policy.xml and changed threads to 1. I verified with convert -list resource that "Thread" is showing 1, yet each convert process is taking up to 900% of our cpu, or 9 of our 12 cpu cores. Even tried export MAGICK_THREAD_LIMIT=1, no change. Any other suggestions?
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magick
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Re: CPU Usage (again)

Post by magick »

Curious. We cannot reproduce the problem:
  • -> time convert logo.png -negate null:
    3.981u 0.700s 0:04.12 599.0% 0+0k 0+0io 0pf+0w
    ->export MAGICK_THREAD_LIMIT=1
    -> time convert logo.png -negate null:
    7.078u 0.633s 0:9.03 97.6% 0+0k 0+0io 0pf+0w
A sure way to ensure only 1 thread is to build ImageMagick from source and disable OpenMP with the -disable-openmp configure script command line.
Prosperent
Posts: 5
Joined: 2011-09-29T10:01:56-07:00
Authentication code: 8675308

Re: CPU Usage (again)

Post by Prosperent »

Thank you for the fast reply. I'll give that a try ad report back. I'm just using the default yum binaries currently.
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