BenV's notes

You know what’s really annoying?

Try this:

root@Uil:/sys/devices/system/cpu/cpu0/cpufreq:0>echo ondemand > scaling_governor
root@Uil:/sys/devices/system/cpu/cpu0/cpufreq:0>dmesg
[1325843.712549] ondemand governor failed, too long transition latency of HW, fallback to performance governor


Apparently this is caused by the p4-clockmod module.
You know, this piece of junk:

Also known as “CONFIG_X86_P4_CLOCKMOD“.

The reason?
Well, the ondemand and the conservative governors want to be able to switch to a different speed before their calculations become invalid.
The p4-clockmod thing apparently makes the latency of switching so BIG that it becomes impossible. Or so they think.
Which leaves only the sucky powersave and performance governors. (and of course userspace).

The kernel menuconfig help states:

This driver should be only used in exceptional
circumstances when very low power is needed because it causes severe
slowdowns and noticeable latencies. Normally Speedstep should be used
instead.

Lovely. I’ll keep that in mind, thanks.
*enables CONFIG_X86_ACPI_CPUFREQ instead*

Note that when they’re both compiled in (as opposed to modules) the retarded thing seems to go for the clockmod. Just great.