This bug is missing log files that will aid in diagnosing the problem. >From a terminal window please run:
apport-collect 1219548 and then change the status of the bug to 'Confirmed'. If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'. This change has been made by an automated script, maintained by the Ubuntu Kernel Team. ** Changed in: linux (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1219548 Title: sched_autogroup_enabled breaks niceness Status in “linux” package in Ubuntu: Incomplete Bug description: With the default Ubuntu 13.04 sysctl settings and boot parameters, positively niced tasks are very clearly given a larger share of CPU time than they ought to be. The update-apt-xapian-index process, for instance, runs at niceness +19; but it still slows my Celeron M520 laptop to a crawl. Likewise for other positively niced tasks. If, on the other hand, I boot with the 'noautogroup' kernel parameter (which sets kernel.sched_autogroup_enabled to 0), responsiveness is much better when running CPU heavy tasks at positive niceness. In both cases, processes are reported by top and ps as running at the correct niceness; it appears that the nice level is ignored silently. Autogrouping is supposed to provide better responsiveness under some loads, but I believe that breaking nice settings is too high a price. I think it would be a good idea to turn off kernel.sched_autogroup_enabled, until this behavior is fixed upstream. By the way, an important note: modifying the sched_autogroup_enabled sysctl on a running system will usually cause a kernel panic. Autogrouping needs to be turned off using 'noautogroup' as a boot parameter; if you try it using sysctl.conf you will get a nice kernel panic on boot. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1219548/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp