Spotlight introduces a fairely large performance hit on to the system, especially if the files you are working with are both large and have the Spotlight plugin, and thus can be indexed. Performance hit might be less noticable on the desktop system with fast drives, however on my laptop with 4200 rpm drive, and constantly dealing with megabytes of source code and compilations spotlight introduced less of a benefit and more of a hindrance.
So, without further ado, in order to disable spotlight, one has to edit /private/etc/hostconfig, find the line that reads SPOTLIGHT=-YES-, change it to SPOTLIGHT=-NO-, and rebooot.
This will prevent MetaData Service, / System / Library / Frameworks / CoreServices.framework / Versions / A / Frameworks / Metadata.framework / Versions / A / Support / mds from starting on boot time.
Note that this will not disable file change notifications in the kernel, as can be checked using Amit Singh’s fslogger. On the same page there is some more in depth information on the kernel notification service that Spotlight (and fslogger) subscribe to.
A perty GUI called Spotless was written by someone, but I am not sure I’d trust a GUI to parse and edit a text file.
If you want to get rid of the looking glass icon in the top right hand corner as well, you might want to either remove (perferably just move out of place) or chmod -R 0000 /System/Library/CoreServices/Search.bundle (Key file. Actual parts of Spotlight are: /Library/Spotlight /System/Library/Spotlight /System/Library/CoreServices/Search.bundle /System/Library/PreferencePanes/Spotlight.prefPane /System/Library/Services/Spotlight.service /System/Library/Contextual Menu Items/SpotlightCM.plugin /System/Library/StartupItems/Metadata plus /usr/bin/md*, although I’d argue that metadata tools in /usr/bin/md* are actually useful.)
Changing permissions means that if at some point you want to undo the changes, you can always repair permissions. In any case, little looking glass in the corner doesn’t bother me much.
Technically one can probably selectively start and stop Spotlight by killing or startng mds and mdimport, however a way Apple recommends is using mdutil -i off / to turn off indexing of the boot volume (ie existing databases would be preserved and accessible through spotlight).
If you ever want to blow away your Spotlight database, and force reindexing (assuming mds/mdimport run), you can do mdutil -i off /, mdutil -E / , mdutil -i on /
Note: Apprently killing spotlight interferes with find in Finder and in Mail.app. As I never use either (locate or find . -name “*foo*” -print on the command line is much more powerful, plus gives me an -exec stuff {} \; option), it doesn’t bother me, however ocdinsomniac has some nice additional information and a script that purports reverting Finder’s find to the Panther style behavior.
