This bad behavior seems to have been caused by issues with futex system calls. Here's the most detailed description I've seen so far, including a small test program that can be used to replicate the behavior (I haven't tried it since it modifies the system time):
https://lwn.net/Articles/504658/ Rather than rebooting, simply setting the system time manually or finding some other way to call settimeofday() would have also restored normal behavior. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1019708 Title: Firefox pegs CPU usage immediately, even in safe mode Status in “firefox” package in Ubuntu: Confirmed Bug description: After updating to Firefox 13.0.1 (13.0.1+build1-0ubuntu0.11.10.1), the browser immediately starts using large amounts of CPU time (50 to 100%), even if I start the browser in "safe mode" with plugins and other features disabled. CPU usage remains consistently high as I browse around to other places. My home page is "about:startpage", the Ubuntu standard. This should not happen. CPU usage should be at or near zero upon loading a simple page like that. [mike@3po][~]$ lsb_release -rd Description: Ubuntu 11.10 Release: 11.10 [mike@3po][~]$ apt-cache policy firefox firefox: Installed: 13.0.1+build1-0ubuntu0.11.10.1 Candidate: 13.0.1+build1-0ubuntu0.11.10.1 Version table: *** 13.0.1+build1-0ubuntu0.11.10.1 0 500 http://us.archive.ubuntu.com/ubuntu/ oneiric-updates/main amd64 Packages 500 http://security.ubuntu.com/ubuntu/ oneiric-security/main amd64 Packages 100 /var/lib/dpkg/status 7.0.1+build1+nobinonly-0ubuntu2 0 500 http://us.archive.ubuntu.com/ubuntu/ oneiric/main amd64 Packages To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1019708/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
