System processes hogging my CPU


Crotchety UI Nitpicker
I just noticed a few system processes start hogging my CPU and making my disk thrash out of nowhere for about 10 minutes. I opened Activity Monitor, and saw that find, a process owned by "nobody" (not root or my user), was the primary culprit. I'd never seen it before, so I quit it.

Then sort and makewhatis (both owned by root, IIRC) popped up and starting hogging my CPU for a few minutes.

What are these processes, and why are they executing randomly and wreaking havoc on my performance? I wasn't doing anything that could be reasonably expected to execute a process called "find" when this happened. I was just minding my own business, playing cards online.

I know there are a lot of questions about mysterious system processes, and 90% of the time they're nothing to worry about, but it still bugs me. Does anyone know of an up-to-date site that explains these things? is a nice resource, but it's outdated and very incomplete.