CPU Governor

By default Linux uses the 'powersave' CPU governor. On 100G hosts, we've seen throughput increase by up by 30% by changing to the 'performance' governor instead.

The command to set this is one of the following:

  • For most newer Linux releases:
cpupower frequency-set -g performance
  • For some older Debian/Ubuntu systems:
cpufreq-set -r -g performance

To confirm what governor you are using, you can use one of these commands:

cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
cpupower -c 0-N frequency-info  (where N is the number of cores)

To watch the CPU governor in action, you can do this:

watch -n 1 grep MHz /proc/cpuinfo

To see the range of possible clock speeds for your CPUs, you can use the lscpu command. 

You can also set the default CPU governor in the BIOS. Note that if you manually set the CPU power setting in the BIOS, then these commands may not work. 

 Reference: CPU Frequency Scaling