On a UNIX system, you could use the top utility to inspect the memory usage, if the administrator has installed it of course.
I suspect that your machine has a single processor, which means that all running processes on the machine share the same CPU. Unless your system has multiple CPU's, forking is not going to speed up processing of your programs, but rather make them slower because of memory usage and task switching overheads.
Unless your system has multiple CPU's, forking is not going to speed up processing of your programs, but rather make them slower because of memory usage and task switching overheads.
Having more processes doing the work gives you a bigger share of timeslice. Chances are that CPU loading is not the problem. I/O latency is a more likely culprit, whether that is from explicit IO calls or vm swapping.