grosser/parallel — pull request #23 by jkamenik (2012-01-06 18:38:45+00:00)
Title: Count physical CPUs on OS X

I have an 2011 MacBook Pro with 8 CPUs, 4 physical and 4 virtual. I use parallel through parallel_test, but I always have to pass `parallel:spec[4]` otherwise the virtual cores fight the physical cores and the tests take longer then not including the virtual cores at all.

Baseline (1 cpu, 174 tests): 47s
All cores (8 cpus, 174 tests): 23s
Physical only (4 cpus, 174 tests): 18s