cstate

Disable CPU c-states on Intel i7's, and maybe other intel CPU's

In order to save energy when the CPU is idle, the CPU can be commanded to enter a low-power mode. Each CPU has several power modes and they are collectively called “C-states” or “C-modes.”, This can be applied by the CPU itself or controlled from the Kernel.

This module allows you to temporarily disable these modes.

I have found this useful in assisting with benchmark tests that would fluctuate due to these power saving modes.

To confirm that this is working, you can use i7z if you have an Intel i7 to see the current utilisation for each core, in each C-state.

NOTE: This module reads /dev/cpu_dma_latency which requires root. Be careful :]

Usage

$ sudo cstate-disable

API

const cstate = require('cstate');
cstate.disable((err) => console.log(err));
cstate.enable((err) => console.log(err));