Public bug reported: While trying to investigate increased load (4.0+) after upgrading to Oneiric, I found in syslog that the 01cpu_online script was hanging and backtracing. Apparently, disabling it brings load down to acceptable levels again.
Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730184] INFO: task 01cpu_online:3670 blocked for more than 120 seconds. Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730190] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730194] 01cpu_online D ffffffff81605060 0 3670 3653 0x00000000 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730200] ffff88020e311bb8 0000000000000086 ffffffff81aab780 0000000000000001 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730205] ffff88020e311fd8 ffff88020e311fd8 ffff88020e311fd8 0000000000012a40 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730210] ffff88022fa78000 ffff880226bbc560 ffff88020e311bb8 7fffffffffffffff Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730215] Call Trace: Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730226] [<ffffffff815e8555>] schedule_timeout+0x2a5/0x320 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730231] [<ffffffff815e7fbf>] wait_for_common+0xdf/0x180 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730236] [<ffffffff810572d0>] ? try_to_wake_up+0x200/0x200 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730240] [<ffffffff815e813d>] wait_for_completion+0x1d/0x20 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730245] [<ffffffff81081226>] kthread_stop+0x46/0x110 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730251] [<ffffffff815ce9d0>] cpu_stop_cpu_callback+0x11b/0x18d Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730256] [<ffffffff815edcfd>] notifier_call_chain+0x4d/0x70 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730261] [<ffffffff810872ae>] __raw_notifier_call_chain+0xe/0x10 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730265] [<ffffffff810605c0>] __cpu_notify+0x20/0x40 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730269] [<ffffffff81060715>] cpu_notify_nofail+0x15/0x20 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730274] [<ffffffff815b8c08>] _cpu_down+0x1d8/0x270 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730278] [<ffffffff815b8cd7>] cpu_down+0x37/0x50 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730282] [<ffffffff815ba7af>] store_online+0x5f/0xb8 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730287] [<ffffffff813cc3c8>] sysdev_store+0x18/0x30 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730292] [<ffffffff811d6c1f>] sysfs_write_file+0xef/0x170 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730298] [<ffffffff81167793>] vfs_write+0xb3/0x180 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730302] [<ffffffff81167aba>] sys_write+0x4a/0x90 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730307] [<ffffffff815f21c2>] system_call_fastpath+0x16/0x1b Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730310] INFO: task kworker/1:2:3672 blocked for more than 120 seconds. Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730313] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730316] kworker/1:2 D ffffffff81605120 0 3672 2 0x00000000 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730321] ffff8801f4cbbee0 0000000000000046 0000000000000000 0000000300000000 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730326] ffff8801f4cbbfd8 ffff8801f4cbbfd8 ffff8801f4cbbfd8 0000000000012a40 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730330] ffffffff81a0b020 ffff8801fa032e40 ffff8801f4cbbee0 ffff88020e311c40 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730335] Call Trace: Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730339] [<ffffffff8107cbc0>] ? manage_workers.isra.30+0x130/0x130 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730343] [<ffffffff810811b3>] kthread+0x73/0xa0 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730347] [<ffffffff815f32e4>] kernel_thread_helper+0x4/0x10 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730351] [<ffffffff81081140>] ? flush_kthread_worker+0xa0/0xa0 Sep 5 13:35:20 sidnei-laptop kernel: [ 360.730355] [<ffffffff815f32e0>] ? gs_change+0x13/0x13 ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: powernap 2.14-0ubuntu2 ProcVersionSignature: Ubuntu 3.0.0-10.16-generic 3.0.4 Uname: Linux 3.0.0-10-generic x86_64 NonfreeKernelModules: nvidia wl Architecture: amd64 Date: Mon Sep 5 13:38:27 2011 InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Alpha amd64 (20110815) PackageArchitecture: all SourcePackage: powernap UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: powernap (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug oneiric -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/841967 Title: 01cpu_online script hangs, backtraces, bumps load To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/powernap/+bug/841967/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs