Home > Linux > get second cpu core enabled after s2ram suspend

get second cpu core enabled after s2ram suspend

September 1st, 2009

Time of holidays is out, time to get back to work. So I have started back work, but one thing made me curious – second core of my CPU was shown as off after resuming from suspend.

Checking CPU state through /sys/devices/system/cpu/cpu1/online shows 1 so the cpu is up, but it has no frequency – this is quite weird.
After some searching I have found that this is probably bug in kernel, another day I have found out that reloading module acpi_cpufreq should resolve this issue and it really did.

Knowing what is the reason I have started thinking how to make the process more automatic, so it is quite easy, just modify /usr/lib/pm-utils/defaults – in variable SUSPEND_MODULES add acpi_cpufreq like this:


Now after resume I can see back my cpu frequency, hope you can too.

By the way I see that /usr/lib/pm-utils/defaults is very important, I have to find a way to make editing it more convenient.

Categories: Linux Tags: , , , , ,
Comments are closed.