Disabling Spotlight (mds) on Mac OS X (Snow Leopard)

I run a lot of command line scripts on my laptop - some of which can run for hours. I want to continue using the machine for reading mail, etc., but I don't want any other intensive task sucking up the cpu cycles. So I shut down iTunes, don't watch any videos, etc.

But sometimes I see some other process taking all my cycles. The odds are that it is either something to do with Flash or it is a process called mds.

mds is the indexing software that powers Spotlight - the built in Mac search facility.

I suspect that when I'm generating gigabytes of data and hundreds of files in one of my compute jobs, mds is responding by trying to index them at the same time.

I don't use spotlight at all, so let's turn it off and see if that helps.

This turns it off:
$ sudo mdutil -a -i off 

This turns it back on:
$ sudo mdutil -a -i on

Turning it back on will presumably trigger a big mds run as it plays catch up, so run this command only when you can afford the cycles.