Incredibly slow conversion

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smantscheff
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Joined: 2010-10-19T03:07:36-07:00
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Incredibly slow conversion

Post by smantscheff »

I just installed imagemagick on Ubuntu Linux (Kernel: 2.6.18-028stab070.2, x86_64 GNU/Linux)

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Version: ImageMagick 6.5.7-8 2009-11-26 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2009 ImageMagick Studio LLC
Features: OpenMP
Now a resize of a small GIF file takes nearly 25 seconds:

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time convert  -resize 100x100 01.gif xx.gif

real    0m24.808s
user    0m9.636s
sys     0m0.116s
The image is a GIF with 33 kB. The same problem occurs with other source files and target formats. The machine has lots of free RAM:

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free
             total       used       free     shared    buffers     cached
Mem:     109036776     123604  108913172          0          0          0
-/+ buffers/cache:     123604  108913172
Swap:            0          0          0
When running convert the average processor load rises from under 0.05 to above 10.
What can I do about this performance problem? I have been using convert on several installations for some years now but never encountered such a poor performance with it.
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magick
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Re: Incredibly slow conversion

Post by magick »

It looks like you have a buggy libgomp. Disable OpenMP with the -disable-openmp configure script command line option:
  • cd ImageMagick-6.6.5-0
    ./configure --disable-openmp
    make install
    time convert -resize 100x100 01.gif xx.gif
smantscheff
Posts: 7
Joined: 2010-10-19T03:07:36-07:00
Authentication code: 8675308

Re: Incredibly slow conversion

Post by smantscheff »

Thanks a lot.
After de-installing the ubuntu package and re-compiling from source code without the openMP option it works. With openMP it does not. I don't even know what openMP stands for. But conversion works, and that's what I need it for.
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