I use an external RAID device on my Mac. I’m constantly frustrated that when it’s connected and I go to use Spotlight I have to wait for it to spin up before Spotlight gives me a result.

Spotlight is useful for quickly searching for files, but also doing quick calculations etc. Say I need to know what $100 is in Sterling, I can just hit command-space and type $100 and it’ll tell me right away. Waiting several seconds while my RAID spins up kills Spotlight’s immediacy which is its key function.

Luckily though it’s simple enough to tell Spotlight to disable indexing for any mounted volume you chose. If you have the same problem pop open a terminal and do the following:

$ mdutil -s /Volumes/<VolumeName>

Indexing enabled. 

> sudo mdutil -i off -d /Volumes/<VolumeName>

Indexing disabled.

> mdutil -s /Volumes/<VolumeName>

Indexing disabled.

Note that clearly this will mean Spotlight is no longer indexing the volume. That means you’ll not see results from that volume in your Spotlight search results (which is the desired outcome for me).