System becomes unresponsive during normal usage

[Jesse Mazis]

The system becomes unresponsive (including stuttering audio, slow mouse cursor, freezing) after an hour or so of usage (sometimes more and sometimes less). Usage at the time was a web browser idling (observed with both Chromium and Firefox) and a music player (Clementine) in the background. There were no CPU intensive applications running at the time.

I was able to capture cpu usage during an episode with the following command (nice set to -20).:
'while true; do ps -eo pcpu,pid,user,args | sort -k 1 -nr | head -30 >> logfile; echo -e "\n"`date` >> logfile; sync; sleep 1; done'
Attached is an excerpt from the generated log file.

Ubuntu Version:
Ubuntu Vivid Vervet (development branch) 15.04

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: xorg 1:7.7+7ubuntu4
ProcVersionSignature: Ubuntu 3.19.0-12.12-generic 3.19.3
Uname: Linux 3.19.0-12-generic x86_64
ApportVersion: 2.17-0ubuntu1
Architecture: amd64
CurrentDesktop: KDE
Date: Wed Apr 8 20:15:52 2015
EcryptfsInUse: Yes
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Alberto Salvia Novella (es20490446e)]

Please:

1. Report to <https://bugs.freedesktop.org/>.
2. Paste the new report URL here.
3. Set this bug status back to "confirmed".

Thank you.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[penalvch (penalvch)]

Jesse Mazis, thank you for reporting this and helping make Ubuntu better.

Could you please run the following command once from a terminal as it will automatically gather and attach updated debug information to this report:
apport-collect -p xorg 1441570

Please ensure you have the package xdiagnose installed, and that you click the Yes button for attaching additional debugging information.

When reporting xorg related bugs in the future, please do so via the above method. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[Launchpad Janitor (janitor)]

[Expired for xorg (Ubuntu) because there has been no activity for 60 days.]