Thanks for the tip. Really useful command, that one, though not exactly what I was looking for: fs_usage shows the current filesystem usage in realtime, and I don't see a way to have it show say the last ten seconds of calls. I do notice, however, that the Palm Desktop background app does a lot of file access. I'll disable that for now and we'll see if it clears up. There is also a lot of calls to /etc/localtime, but that's from some unnnamed Carbon app, so I'll have to investigate further.