Comment 17 for bug 1579278

Revision history for this message
Doug Smythies (dsmythies) wrote :

>> The preferred governor with the intel_pstate driver is powersave.

> Do you have some references/proof for that? This is contrary to what
> kernel developers say, see comment 1.

In my opinion, that reference is obsolete.

While I don't work for Intel, the intel_pstate CPU frequency driver is pretty much the only thing that I work on, and for a few years now, and through 3 maintainers. Why would Intel expend so much effort on powersave mode, if it were better to merely set performance mode and forget about it? The objective with powersave mode is best energy/ performance tradeoff. There are still issues, yes. For example whenever clock modulation becomes involved. Also, there can be a tendency to incorrectly drive up the CPU frequency. There is work in progress that should address these issues (see: http://askubuntu.com/questions/812530/cpu-frequency-scaling-not-working-as-intended-on-vanilla-ubuntu-16-04/812721#812721 and the reference links therein.)

I'll try to come back, maybe this weekend, with some energy comparison numbers.