powernapd runaway
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
powernap (Ubuntu) |
New
|
Undecided
|
Unassigned |
Bug Description
Very occasionally powernapd runs away on me and starts using almost 100% of available CPU cycles. I'm running version 2.17-0ubuntu2 on i386, Ubuntu 12.04.4. The hardware is a Fujitsu Siemens LifeBook S7020 with BIOS version 1.05.
The last two entries in /var/log/
2014-04-08_12:49:54 WARNING Taking action [/usr/sbin/
2014-04-08_13:54:37 WARNING Taking recover action [/usr/sbin/
I assume that something goes wrong during the transition away from powersave.
Attaching to the running /usr/sbin/powernapd process with gdb yields the following backtrace:
#0 0x002b5416 in __kernel_vsyscall ()
#1 0x00549bd1 in select () at ../sysdeps/
#2 0x080fbdf3 in time_sleep.52928 ()
#3 0x08137591 in PyEval_EvalFrameEx ()
#4 0x08137abc in PyEval_EvalFrameEx ()
#5 0x0813da90 in PyEval_EvalCodeEx ()
#6 0x0813e361 in run_mod ()
#7 0x0813e851 in PyRun_FileExFlags ()
#8 0x08087565 in PyRun_SimpleFil
#9 0x0808909f in Py_Main ()
#10 0x0805eabb in main ()
I'm attaching a few seconds' worth of strace output.
My only workaround so far is to run
service powernap restart
(or equivalent) whenever this happens. Unfortunately I don't know how to reproduce the problem at will.