I was happily doing stuff online when for no good reason everything became incredibly unresponsive - even the mouse cursor took forever to move. I switched to a text console and, in between delays, managed to run top and saw that the process "migration" was taking up all of the CPU. I killed it, but another took its place. I killed that too and got a bunch of errors, but the system became responsive again and I was able to run startx, whereupon the GUI remained up for all of a minute or so before crashing with a segfault. I reset the computer and it seems to be working fine, but I was writing a fairly lengthy post that was lost, and I really want to avoid this happening again. What's migration, why is it hogging CPU and how do I stop it without bringing the whole system down? There is no info, manpage or indeed command for it.
If it helps, it has a very low PID - it was 12 first, then the second instance was 7.
Edit: gah, I forgot the board has a LMDE subforum... sorry about that.