So, what about threads? I've seen Linux versions where they all had the same load as the base process, resulting in a huge load in a multi-threaded server application.
In Linux, running threads that are shown in 'top' (with thread mode 'H' on) to be in state 'R' or 'D' are counted in the load average. You'll definitely see this in programs with a ton of threads, like MySQL or the Java JVM.
If you're not in thread mode in top, this is why you will sometimes see a process consuming > 100% CPU usage.
