Created attachment 273907 [details] output of emerge --info Since gentoo-sources-2.6.37 I experience several kworker threads eating up one core of my cpu like every 4s. I've tried with 2.6.37-r4, 2.6.38, 2.6.38-r5 - always the same picture. (see attachments: screenshot of ksystemmonitor). I've read in other forums that this might be acpi-wakeup-related. Any clues or workarounds? What more information do you need?
Created attachment 273909 [details] Picture of ksystemmonitor - mostly idle, 1px = 0.2s
(In reply to comment #1) > Created attachment 273909 [details] > Picture of ksystemmonitor - mostly idle, 1px = 0.2s We appear to be looking at CPU temperature there.
That is indeed right, this laptop has thermal problems. But it worked well enough with earlier kernels. The second line of system monitor output is cpu-load for both cores. the last line is clock frequency and fan-speed in one.
It would help if you figured out what was causing these spikes. Also, it looks kind of like the generic power consumption problems with recent Linux kernels we've all been reading about in the press about.
I'd like to. How can I "decode" what a kworker thread actually is doing? Another update: I reverted back to gentoo-sources-2.6.37-r4 and those spikes are gone. I used the same config as with the 2.6.38-r5 ("make oldconfig").
Can you try with gentoo-sources-3.0.3? Thanks.
(In reply to comment #5) > I'd like to. How can I "decode" what a kworker thread actually is doing? > > Another update: I reverted back to gentoo-sources-2.6.37-r4 and those spikes > are gone. I used the same config as with the 2.6.38-r5 ("make oldconfig"). Use Kernel Hacking -> Tracers -> Kernel Function Tracer (and friends) to see where the kernel is spending its time. Look at Documentation/trace/ftrace.txt. Its involved, but you'll find it. You can also try PERF_COUNTERS, but that's specific to some process that you might suspect is responsible for heavy sys calls. General setup -> Kernel Performance Events And Counters. You'll need the userland utility tools/perf.
Actually this issue has resolved. I went back to 2.6.37-r4 where I had no problems. Then later on I went to 2.6.38-r6 with no problems either. I have not bothered yet to update the kernel further because of some lack of time. Thank you anyhow.
Ok. I'm closing this for now. If you encounter the same issue with newer kernels, feel free to reopen. Thanks.
