http://bugzilla.kernel.org/show_bug.cgi?id=15106
--- Comment #9 from Ali Gholami Rudi <aliqr...@gmail.com> 2010-02-18 18:06:29 --- After observing it for some time, I think I know how it happens (I don't know much about acpi, so sorry for wrong conclusions): The high cpu usage happens on 43^C. That is the first active cooling temperature. It seems on this temperature the bios generates lots of acpi events and at each event the acpi driver does the same actions again. Below or above this temperature I can control the fan through /sys but at 43^C, it is reset very fast (most of the time so fast that I cannot notice a change in fan speed). About the reported temperature change delay, I think the bios reports the new temperature only when it thinks it is useful to the driver, hence the temperature is not updated till it reaches 43. When it becomes cooler it gets updated to 42 (it won't report a smaller number since it thinks the driver should not care if the temperature is 42^c or say 20^c, since both are lower than the first trip point). The same holds for higher temperatures; it reports 43 till it reaches 53^c. So I think the main bug is in the bios which generates many acpi events when it is close to a trip point temperature. If so, how can it be fixed? Is it possible to ignore acpi events when they are very close to the last one? Or are there better solutions? Thanks, Ali -- Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug. ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ acpi-bugzilla mailing list acpi-bugzilla@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/acpi-bugzilla
