On 8/28/23 17:02, Lazar, Lijo wrote: > [AMD Official Use Only - General] > > > As mentioned with an older version of this series, this is an 'abuse' of > power profile interface. > > This series is oversimplifying what PMFW algorithms are supposed to be doing. > Whatever this series is doing, FW can do it better. > > To explain in simpler terms - it just tries to boost a profile based on ring > type without even knowing how much of activity a job can trigger on a > particular ring. A job scheduled to a GFX ring doesn't deserve a profile > boost unless it can create a certain level of activity. In CPU terms, a job > scheduled to a processor doesn't mean it deserves a frequency boost of that > CPU. At minimum it depends on more details like whether that job is compute > bound or memory bound or memory bound. > > While FW algorithms are designed to do that, this series tries to trivialise > all such things. > > Unless you are able to show the tangible benefits in some terms like > performance, power, or performance per watt, I don't think this should be > the default behaviour where driver tries to override FW just based on job > submissions to rings.
I know at least one tangible benefit this would have: a snappier GNOME desktop with lower input → output latency on many laptops. The bootup default profile doesn't work well for that IME. It should also help for issues like https://gitlab.freedesktop.org/drm/amd/-/issues/1500 . That said, I agree this approach is very aggressive. I think it might be acceptable with AC power, not sure about on battery though. (There might be better performance/power profile mechanisms to hook into than AC vs battery) -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and Xwayland developer
