David M Beazley (http://www.dabeaz.com)
The following visualizations show thread scheduling of CPU-bound threads on a single CPU of a Mac OS-X system (described below). Observe how threads alternate execution in large blocks of time. This is good--you want this kind of behavior to avoid excessive context-switching. If you don't care about OS-X, view the Linux version of this page.
Tests were conducted on the following system: