Apparently doesn't work on Android. At GDC this year I was in a hallway huddle of high-end mobile game devs complaining about how wide parallelism does work on Android because the scheduler stops listening to your affinity requests and just schedules everything in serial on one core so that it can save power on the other three.
I've had huge speedups from poorly-threaded software (thousands of threads, all sharing locks and work) just by running multiple processes and pinning them to specific cores. It was also far more stable that way.
