[Bf-committers] OpenMP on osx

Campbell Barton ideasman42 at gmail.com
Tue Aug 16 13:04:09 CEST 2011

On Tue, Aug 16, 2011 at 8:54 PM, Tobias Kummer <supertoilet at gmx.net> wrote:
> Hey there!
> I just realized that when using an OpenMP enabled build on osx (cmake),
> all simulations and baking run terribly slow. When I compile the same
> revision with OpenMP disabled, it uses one core at 100% and is MUCH
> faster. Can anyone confirm this? Are there known problems with OpenMP on
> OSX?
> Greets,
> Tobi

At the blender institute we had the same problems and it seemed to be
because of the processor (core2's were ok but i7's had performance
problems), rather then rebuilding you can set the OMP_NUM_THREADS
environment variable to 1.

We could make blender detect this on startup and set OMP threads to 1
based on the processor - using a shell script or perhaps it can be
done in blender's main function on startup.

- Campbell

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