thom, thank you for your comment. Regarding the severe performance regression going from 12.04 to 14.04, I would file a new report via a terminal so this could be bisected and dealt with separately via a terminal:
ubuntu-bug xorg
This is a significant bug in Ubuntu. If you need a fix for the bug in previous versions of Ubuntu, please perform as much as possible of the SRU Procedure [1] to bring the need to a developer's attention.
thom, thank you for your comment. Regarding the severe performance regression going from 12.04 to 14.04, I would file a new report via a terminal so this could be bisected and dealt with separately via a terminal:
ubuntu-bug xorg
Regarding the original issue noted in the Bug Description, I am closing this report because as per your comment https:/ /bugs.launchpad .net/ubuntu/ +source/ xserver- xorg-video- nouveau/ +bug/996168/ comments/ 23 the bug has been fixed in the latest development version of Ubuntu - Trusty Tahr.
This is a significant bug in Ubuntu. If you need a fix for the bug in previous versions of Ubuntu, please perform as much as possible of the SRU Procedure [1] to bring the need to a developer's attention.
[1]: https:/ /wiki.ubuntu. com/StableRelea seUpdates# Procedure
Thank you for your understanding.