Spotlight is a great tool for sifting through the files on your Mac's drives to find exactly what you need. It isn't so great, however, when its Index file get corrupted and you don't see all of your files -- or your Mac's fans start spinning incessantly.
If Spotlight is having trouble indexing your hard drive you may see the mds (It's part of Spotlight indexing) process hogging all of your processor. You can check by going to Applications/Utilities and launching Activity Monitor. This handy utility shows how much CPU each app is using, and if you click the Percent column, the apps that are using the most float to the top of the list.
If mds stays at the top, it may be time to force Spotlight to reindex your drives. Here's how:
- Go to Applications/Utilities and launch Terminal
- Enter this command in Terminal: sudo mdutil -E /
- Press Return
- Enter your administrator password when prompted
Reindexing Spotlight can fix search problems and give your fans a rest
Spotlight will trash the old index and start over, which could take a couple days depending on how much data it needs to dig through. Once it finishes, however, your fresh index should be fine and your Spotlight problems should be gone.