On 19 Aug, 05:27, Dave Angel <da...@ieee.org> wrote: > But if you do it that way, it's slower than sequential. And if you have > a multi-core processor, or two processors, or ... then it gets much > slower yet, and slows down other tasks as well. > > With the current GIL implementation, for two CPU-bound tasks, you either > do them sequentially, or make a separate process.
For CPU bound tasks, one should put the bottleneck in C/Fortran/Cython and release the GIL. There is a speed penalty of 200x from using Python instead of C. With a quadcore processor you can gain less than 4x speed-up by parallelizing. If you really care enough about speed to write parallel code, the first thing you should do is migrate the bottleneck to C. -- http://mail.python.org/mailman/listinfo/python-list
