I'm fairly sure this is a duplicate, but I can't find the older version of the bug right now. I also remember many people talking about the problem being the default kernel scheduling algorithm. But let's leave the bug attached to Unity for now because it's possible Unity is indirectly accessing the disk when that really should be avoided (for this very reason).
** Summary changed: - Unity works slow on my powerful PC + Unity works slow during heavy system IO (busy disk or network) ** Also affects: unity Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1000164 Title: Unity works slow during heavy system IO (busy disk or network) To manage notifications about this bug go to: https://bugs.launchpad.net/unity/+bug/1000164/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs