Heya,
A lot of us who write Python code use the multiprocessing module because it's an easy way to distribute the workload among many cpu's. But when you do, please do not allocate all cores to your jobs, because it basically makes a box unavailable to other folks (particularly when your jobs are long-running). You can use the multiprocessing.cpu_count() function to determine the number of available cores and subtract 1 or 2 to make sure that there is some slack available for other processes.
thx!
D