While doing any graphics heavy task, such as playing a game or just watching Netflix via pipelight I was getting frequent pauses, where the entire system would lock up for ~5 seconds.
Dmesg was showing the following whenever it happened:
[drm:i915_set_reset_status] *ERROR* render ring hung inside bo 3.11
It turns out this is related to a bug in Mesa, which has been fixed in 10.0. To update to this in Ubuntu 13.10, add this repository:
sudo add-apt-repository ppa:oibaf/graphics-driversthen:
sudo apt-get update && sudo apt-get dist-upgradeand restart.
Be aware that while these packages seemed stable for me, they could well result in system instability for others. Make sure you know what you're doing and have a recovery plan, or backups should you need to revert. Something like PPA-Purge is likely the trick.