Daniel Arbuckle's Mastering Python

Testing multiple worker processes

The other nose feature we're going to look at is the ability to farm out tests to multiple worker processes and thus spread them across the available CPU cores. To test multiple worker processes, we just have to provide the --processes= command-line option and tell it how many processes to use. If we pass -1 to indicate the number of processes, it uses the detected number of CPU cores, which is probably what we want anyway (refer to the following code example):

So, unless we have a specific reason to do otherwise, we should always just use -1.

If we look carefully at the preceding code example, we can see ...