On Mon, Jan 25, 2021 at 07:37:55PM +0800, Li, Aubrey wrote: > > It's interesting that patch 3 would make any difference on x64 given that > > it's SMT2. The scan depth should have been similar. It's somewhat expected > > that it will not be a universal win, particularly once the utilisation > > is high enough to spill over in sched domains (25%, 50%, 75% utilisation > > being interesting on 4-socket systems). In such cases, double scanning can > > still show improvements for workloads that idle rapidly like tbench and > > hackbench even though it's expensive. The extra scanning gives more time > > for a CPU to go idle enough to be selected which can improve throughput > > but at the cost of wake-up latency, > > aha, sorry for the confusion. Since you and Vincent discussed to drop > patch3, I just mentioned I tested 5 patches with patch3, not patch3 alone. >
Ah, that makes more sense. > > > > Hopefully v4 can be tested as well which is now just a single scan. > > > > Sure, may I know the baseline of v4? > 5.11-rc4. -- Mel Gorman SUSE Labs