Question: I just installed a new version of Mac OS X, namely Snow Leopard. Since the restart, my Mac has been extremely slow, choppy at best. Why is this happening?
Answer: Do not worry, this is the Spotlight search system which is indexing your hard disk drive. It is rebuilding the entire search database, something that can take 10 minutes or a bit more. Even on Mac Pro.
Symptoms include heavy activity for the hard drive and a relatively high percentage of CPU usage if you open the Activity Monitor. In short, everything is slow on your Mac during this specific period of indexing.
The solution may just be to go away from your Mac for 15 to 20 minutes, while it finishes the Spotlight job.
If this happens every time you start up your Mac, then you have a problem with the index files. You may want to eliminate them to force a full rebuild of the index, once and for all.
Dig in the Terminal application to do this, which is located in the Applications > Utilities folder. Since use of command lines can make a few people nervous, you can copy and paste information from here to be sure of what you are doing. Each time you use a command, press Enter on your keyboard to validate it.
Should you be asked for your administrator password at any point, type it and then press the Enter key.
Removing the index from the drive and forcing a rebuild:
sudo mdutil -E /
Do you find Spotlight useless? You can turn it off:
sudo mdutil -a -i off
Turning it back on:
sudo mdutil -a -i on
