[Cbc] mulithreading in cbc

[John Madison]

Howdy folks,
I am working on testing out whether we can increase our solver performance
by multithreading cbc. So far my results with compiling and running under
windows have been not good, so I assume I am doing something wrong. My code
is basically like this:

CbcModel ip(*(coinlp));
ip.setNumberThreads(2);
ip.setAllowablePercentageGap(AllowablePercentageGap);
ip.setMaximumSeconds(maxTime);
ip.branchAndBound();


I tried with 1,2,3,4,5,6,and 8 threads on my quad core machine, but only
noticed any speedup with 2 threads and a dramatic degradation as the number
of threads increased beyond that.

Is there some sample code out there that will show me what I am doing wrong?

Thanks,
John
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