About a week ago spotlight started reindexing my disk all of a sudden, without any provocation as far as I can tell. It took many hours to complete (MBA 1.8G i7 256ssd).
Then, today, again it started reindexing all over again. Only today, around the time that it started reindexing, I briefly got a low disk space warning and then immediately emptied the trash which accumulated many gigs -- this may or may not be related.
Why is this happening and how can I prevent it?