Make Spotlight indexing use less CPU?
You cannot configure how fast Spotlight will index files. Normally, it should auto-throttle itself and not cause massive CPU usage (unless fully rebuilding indexes or doing first-time indexing).

If you run into trouble with Sophos and Spotlight, you could tell Sophos to ignore Spotlight's metadata folder. Also, note that there a lot of grief about Sophos interfering with spotlight: https://discussions.apple.com/thread/3562174?start=0&amp;tstart=0