I've been doing a bunch of kernel-compiling recently and I've switched between schedulers from compile to compile to compare. See https://www.kernel.org/doc/html/v6.6/admin-guide/pm/cpufreq.html for background info. All frequencies in khz. On my machine...
* bios_limit == 2901000 * scaling_available_frequencies == 2901000 2900000 2700000 2600000 2400000 2300000 2100000 2000000 1800000 1700000 1500000 1400000 1200000 1100000 900000 800000 * scaling_available_governors == conservative ondemand userspace powersave performance schedutil NOTE: You must build the governors you want into the kernel make menuconfig Power management and ACPI options CPU Frequency scaling ...and select the desired governors. *YOUR NUMBERS AND GOVERNORS WILL BE DIFFERENT* When rebuilding kernels, I wanted to do "apples-to-apples" comparisons so I would... * make menuconfig (in /usr/src/linux) * cp .config .. (*VERY IMPORTANT*) * make mrproper (initialize stuff in /usr/src/linux to a sane state) * cp ../.config . (restore .config which got wiped by "make mrproper") * (build new kernel, "time blah blah blah") I've cobbled together a bash script that can list and set cpu frequencies and governors. Note that root or sudo permission is needed to set anything, because the script is writing to the /sys/ filesystem. I would hover the mouse pointer over the ICEWM toolbar CPU widget to get CPU data. * select governor "userspace" and speed 2900000 * computer "idling"; CPU speed approx 2.900 ghz and temp 28 C * compiling kernel; CPU speed approx 2.900 ghz and temp 35-to-37 C * kernel takes 20 minutes to build * select governor "schedutil" * computer "idling"; CPU speed approx 0.800 ghz and temp 28 C * compiling kernel; CPU speed approx 4.200 ghz and temp 46-to-48 C * kernel takes 15 minutes to build Is that a dangerously high CPU temperature? Building the kernel 5 minutes faster is a minor improvement. -- Roses are red Roses are blue Depending on their velocity Relative to you
