On Thu, 3 Jul 2014 16:59:17 +0100 Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: > On Thu, Jul 03, 2014 at 08:49:22AM -0700, Jesse Barnes wrote: > > On Thu, 3 Jul 2014 15:29:26 +0100 > > Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: > > > > > Baytrail uses the RPS wait-boosting mechanism of Sandybridge+ but also has > > > a very lax downclocking strategy (upclock if more than 90% busy over 76ms, > > > downclock if less than 70% busy over 450ms). This causes Baytrail to use > > > maximum clocks, and for them to stay high, when doing simple tasks such as > > > scrolling through webpages. However, we can take a leaf out of the same > > > wait-boost mechansim and apply the aggressive downclocking strategy from > > > Sandybridge+ as well. > > > > > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > > --- > > > > We really need a thorough test suite to cover stuff like this, mapping > > frequency, power, and total energy over a big set of workloads to make > > sure we're not adding big regressions. > > > > I know you have the cairo traces, but did you also try this with a GL > > benchmark suite? > > glxgears went from max clocks to min clocks whilst hitting 60fps. > > Note that you first have to disable the cmdparser to make the machine > pleasant to use. > > > I'm like the change (well you did mix in a cleanup to > > set_rps_thresholds), > > Actually, I left it replicated originally because they used different > strategies at one point and keeping it separate eased experimentation. > > The only thing that is missing is a comment to explain that I found I > needed to rewrite the control register every time for the change in > thresholds to take effect. > > > I just want us to get better at collecting numbers > > for this stuff... > > It's not like we have pretty tools to overlay realtime GPU usage and > bottlenecks... Yeah I know we have nice tools, I'm just thinking of data over time so we can see regressions easily etc. The power stuff QA collects ought to catch it, but I don't think we've done specific runs with turbo changes recently; would be good to get Wendy to do that for this patch and see what happens. -- Jesse Barnes, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
