On Sun, 23 September, 2007 10:27 pm, Ben Liblit wrote: > PowerTOP reports that one of the top wakeup causes on my desktop machine > is: > > 27.0% ( 59.8) sh : queue_delayed_work_on (delayed_work_timer_fn) > > I can use "lsof /bin/sh" to figure out what the live sh processes are. > During a typical desktop login session I see just two: one for the > firefox wrapper script and one for the thunderbird wrapper script. If I > exit both of those applications, "lsof /bin/sh" lists *zero* processes > running sh. > > And yet ... "sh : queue_delayed_work_on (delayed_work_timer_fn)" still > appears at the top of PowerTOP's wakeup causes list! > > Any ideas what's going on here? Where are these phantom sh processes > coming from that disturb my CPU's slumber?
Sorry if this is a dupe. It's probably because a shell script somewhere, sometime, asked the kernel to do something that involves polling. A likely culprit would be if you're using the ondemand frequency governor on a 2.6.22 kernel. This is enabled by echo'ing a value into a sysfs file, and echo is a shell builtin so the sh binary gets blamed. The ondemand governor has been fixed in recent 2.6.23-rc versions. This is a general problem with powertop (or rather, the kernel interface it uses): with interpreted programs like shell scripts you just get the name of the interpreter, not the full commandline which would include the interpreted program. It would be more obvious if powertop showed the shell script responsible, e.g. on Ubuntu the shell script responsible for cpufreq would be "/etc/init.d/powernowd", and that would give you a better starting point. -- A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail? _______________________________________________ Power mailing list [email protected] http://www.bughost.org/mailman/listinfo/power
