I have a software RAID 5 partition on LVM in Ubuntu (desktop, actually, but I'm using it as a server). I have been rsyncing a ton of data to it, and the computer was hard freezing, as in I needed to press "Reset".
So I thought it was rsync. But I decided I'd try a dd if=/dev/zero of=/path/to/raid5 and sure enough, the computer locked up. Did an identical dd to a JBOD partition on the same machine, and it didn't crash.
Assuming a clean RAID5 partition, tri-core processor 2GB of ram, 6GB swap, what could be causing this?
Edit: I've ruled out memory; I ran an 8 hour memtest without a crash.
04/26/2011 Edit: I've ruled out Ubuntu alone; the error occurred in Debian 6 stable. It's either hardware or an upstream bug.