strange disk access

[BTP]

Hello, I hope maybe one of you can point me in the right direction to do my research here...

on my debian system (on my laptop) for the first time and for no reason my disk accesses started going crazy and really bogging down the system for about half a minute. I couldn't even open a terminal window to check the process tasks...

How would I go about tracking down exactly what this disk access was all about? It might have been just swapping but I don't know if it would get that bad and whether it normally swaps without such problems...

Bart