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10/06/11 06:14am

I have a Map that is taking too long, and since it's embarrassingly parallel, I thought I'd try the ParallelMap function.

The statement looks like this:
data = ParallelMap[(counter++; {p, #1, g[p, #1, a, b]}) &, mesh];

I've shared the counter variable using

I haven't distributed any definitions, since my understanding is that ParallelMap is clever enough to share everything that's necessary. Is that correct?

g is a fairly complicated function, which does use a few different global variables.

At the moment, it appears to run the function g[] sequentially on the master kernal - if I put a Print[$KernalID] in the virtual function above, I get the IDs of the 4 sub-kernals, but if I put Print[$KernalID] inside the function g, I get the ID of the master kernal. It takes as long to run as with just regular Map.

I don't get any errors or warnings.

Any ideas?


Wade (PhD student, Australia)

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Subject (listing for 'Parallelising - troubleshooting')
Author Date Posted
Parallelising - troubleshooting Wade 10/06/11 06:14am
Re: Parallelising - troubleshooting qm2008q 11/25/11 07:16am
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