Since around a week ago, I've been having a lot of cases where the programs go on disk sleep doing the most menial tasks (scrolling text or opening a different tab in the web browser, minimising and restoring applications, etc.). During those times even the mouse cursor gets stuck. It doesn't last long, but it gets very annoying very fast. It never happened before that time. The log doesn't seem to contain anything relevant to the issue.

Has anyone else experienced anything similar recently? Any ideas on what I could try to solve the problem?

I'm using openSUSE 13.1, KDE, Btrfs. One thing I could try is going back to an older snapshot of the system with snapper, but I wonder if there might be something else I could try before that...