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Most nights, some time in the hour of 3AM my xorg process will increase to 100% cpu and gpu load will also increase to 100%. The process also becomes unkillable. I cannot sudo kill -9 it or get back control with sudo service lightdm restart. I also cannot switch to to a tty screen with ctrl + alt + f1. To reboot I have to log in with ssh, but this is not perfect because if I reboot while it is doing this my ZFS pool will fail to mount when it comes back up ( that is where my /home is ).

Does anyone have any ideas as to why I can't stop and restart xorg, or even better, know why this is happening?


NOTE: For anyone who comes looking for the same problem. I disabled catalyst AI and made it through the night. I've been up for 1 day 3 hours now. My record for this month is 2 days and 19 hours without a problem. My all time record is 6 days without a crash. I'll post here if it crashes again or I'm able to set a new record.

UPDATE: My computer crashed today at 4:32AM. I rebooted at 9:30 and went to a 1 hour lecture, when I came back it had crashed again. I have reverted to the open source drivers for now =(

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For how long does the high load lasts? – MestreLion Sep 19 '12 at 19:36
Until I reboot, the keyboard and mouse are totally unresponsive when it is happening so I usually reboot as soon as I notice. The longest I think I've ever left it is 18 hours though. – chew socks Sep 19 '12 at 20:25
Things that happens everyday at the same time suggests a cron/anacron job. You may check you schedule and see if there's any daily command that may lead to this issue. Also, check the system logs, they will surely provide helpful insights – MestreLion Sep 19 '12 at 21:33
I was about to report that nothing happened out of the ordinary in the log around that time, as in the only cron jobs happening happen every half hour, but then I noticed a kernel dump about 20 minutes after the crash – chew socks Sep 19 '12 at 22:07

Judging by your log, it looks like FGLRX, AMD's proprietary video driver for ATI Radeon cards, is the culprit.

And it...

... looks like ...

.. you're not ...

... alone.

After reading those (looong) pages, not one yet proposed a definitive solution. So the approaches I suggest you are:

  • Upgrade your Catalyst to the latest version. IIRC, it's 12.6 now. I also have an ATI card, a Radeon HD 7770, and it works great with 12.6.

  • Try other versions too. 11.4, 12.4. Download package from ubuntu or build it yourself directly from AMD.

  • Or simply forget about FGLRX and go with the default, open-source, usually trouble-free drivers. Just notice that while it gives less headaches than AMD's proprietary driver, it is considerably slower for high-end 3D games. But for "normal", non-gaming use you won't notice any difference.

Gook Luck!

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Thanks for the response, that's interesting that you don't have any problems. I'm using an HD 5770, the large fan is the only reason I don't want to switch to the open source drivers ( fan runs too fast in open source drivers ) seeing as this is an always on computer in my apartment. I built 12.6 a few days ago, before that I was just using the package from Ubuntu repos. – chew socks Sep 19 '12 at 23:06
After I saw the line about ASIC hang I started googling and found some similar pages. One person suggested disabling Catalyst AI. We'll see if that helps. – chew socks Sep 19 '12 at 23:09
I have Nvidia drivers and I have same issue :( – Jan Netherdrake Oct 16 '13 at 17:42

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