https://bugzilla.novell.com/show_bug.cgi?id=333733#c1 --- Comment #1 from r myster 2007-10-19 13:44:25 MST --- Created an attachment (id=179521) --> (https://bugzilla.novell.com/attachment.cgi?id=179521) suspend-resume logs for before & after using "nohz=off" boot option openSuSE 10.3 2.6.22.9-0.4-default (latest kernel from update) Similar story here. After a suspend & resume, the ksoftirqd/0 and migration/0 jumps to 9999% cpu use(shown under top). Unlike the case above, initially after the resume, everything seems fine but as soon some other application is opened, the usage jumps. The cpu usage jump also happens after a couple minutes with no activity. All I could find on ksoftirqd was this blip from the manual: ksoftirqd is a per-cpu kernel thread that runs when the machine is under heavy soft-interrupt load. Soft interrupts are normally serviced on return from a hard interrupt, but it's possible for soft interrupts to be triggered more quickly than they can be serviced. If a soft interrupt is triggered for a second time while soft interrupts are being handled, the ksoftirq daemon is triggered to handle the soft interrupts in process context. If ksoftirqd is taking more than a tiny percentage of CPU time, this indicates the machine is under heavy soft interrupt load. I did run across another thread discussing high cpu useage on a virtual machine(http://marc.info/?l=vbox-users&m=119012208118392&w=2) and the solution there was to use the "nohz=off" boot option(something to do with the tickless kernel) which seems to fix the issue. Whether it has introduced other side effects is yet unknown. The attached gzip filepm-suspend-logs.tar.gz) contains pm-suspend logs for both the high cpu result after resume case and one for a suspend-resume cycle after a reboot using the "nohz=off" boot option. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733#c2 --- Comment #2 from Aaron Digulla 2007-10-23 12:16:56 MST --- Adding "nohz=off" to the kernel boot options solves the issue for me. Now, it would be interesting to find out what is drowning the system in interrupts after a suspend. Any pointers? -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733 Pavel Machek changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |ASSIGNED -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733#c5 Aaron Digulla changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEEDINFO |ASSIGNED Info Provider|digulla@hepe.com | --- Comment #5 from Aaron Digulla 2007-11-02 13:47:49 MST --- I tried with 2.6.24-rc1: - It was a bit complicated to compile the kernel; make oldconfig was asking a lot of questions (for example about /sbin/hotplug). If you could provide a precompiled kernel tar with modules, I could try that to make sure I didn't break anything by giving the wrong answer to one of the options. - After the install, the computer booted with and without the "nohz=off" option. - Suspend to disk (S2D) with "nohz=off": Suspend works, computer shuts down as it should (green screen, bar fills, shutdown). When I resume, I see that it loads the pages back, the screen is rest and then it hangs. Keyboard works and I could use SysRq to reboot. - Without nohz=off: Computer hangs in "ZZ" screen (green bar fills completely but computer doesn't switch off). Keyboard is okay (Numlock still works). When I reboot manually, the computer hangs in the resume after loading the initial pages (just like before). Therefore, my self compiled 24-rc1 doesn't work at all. With nohz=off, I could suspend and resume more than 10 times without problems. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733 User pavel@novell.com added comment https://bugzilla.novell.com/show_bug.cgi?id=333733#c7 Pavel Machek changed: What |Removed |Added ---------------------------------------------------------------------------- Severity|Normal |Minor --- Comment #7 from Pavel Machek 2007-12-25 05:38:29 MST --- Ok, keep nohz=off for now. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733 Pavel Machek changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |NEEDINFO Info Provider| |digulla@hepe.com -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733 User reinhard.fobbe@arcor.de added comment https://bugzilla.novell.com/show_bug.cgi?id=333733#c10 Reinhard Fobbe changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |reinhard.fobbe@arcor.de --- Comment #10 from Reinhard Fobbe 2008-05-27 12:07:49 MDT --- I just installed OpenSuse 10.3 on LG TX Express and updated everything online. Then I started to see ksoftirqd consuming around 40% cpu after starting the wireless connection via nm-applet 0.6.5.Closing the wireless connection or using a wired connecting reduced the cpu immediately. Setting "nohz=off" solved this - many thanks. This problem is easy to reproduce on 2.6.22.17-0.1-default. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733 User pavel@novell.com added comment https://bugzilla.novell.com/show_bug.cgi?id=333733#c12 --- Comment #12 from Pavel Machek 2008-05-28 02:02:57 MDT --- Reinhard: you should definitely open a new bug. _But_: it would be great to test it on opensuse11 (available in beta now). Or at least try it on that kernel. There's chance that it is fixed there, and we can work on fixing it there. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=333733 User pavel@novell.com added comment https://bugzilla.novell.com/show_bug.cgi?id=333733#c14 --- Comment #14 from Pavel Machek 2008-06-23 02:07:40 MDT --- Ok, thanks for letting us know. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.