Re: [PATCH 3/4] sched/fair: Do not replace recent_used_cpu with the new target

2020-12-11 Thread Mel Gorman
On Fri, Dec 11, 2020 at 05:34:43PM +0800, Hillf Danton wrote: > On Fri, 11 Dec 2020 09:02:28 + Mel Gorman wrote: > >On Fri, Dec 11, 2020 at 02:25:42PM +0800, Hillf Danton wrote: > >> On Tue, 8 Dec 2020 15:35:00 + Mel Gorman wrote: > >> > @@ -6277,17 +6277,13 @@ static int

Re: [PATCH 3/4] sched/fair: Do not replace recent_used_cpu with the new target

2020-12-11 Thread Mel Gorman
On Fri, Dec 11, 2020 at 02:25:42PM +0800, Hillf Danton wrote: > On Tue, 8 Dec 2020 15:35:00 + Mel Gorman wrote: > > @@ -6277,17 +6277,13 @@ static int select_idle_sibling(struct task_struct > > *p, int prev, int target) > > > > /* Check a recently used CPU as a potential idle

Re: [PATCH 3/4] sched/fair: Do not replace recent_used_cpu with the new target

2020-12-10 Thread Vincent Guittot
On Tue, 8 Dec 2020 at 17:14, Vincent Guittot wrote: > > On Tue, 8 Dec 2020 at 16:35, Mel Gorman wrote: > > > > After select_idle_sibling, p->recent_used_cpu is set to the > > new target. However on the next wakeup, prev will be the same as > > recent_used_cpu unless the load balancer has moved

Re: [PATCH 3/4] sched/fair: Do not replace recent_used_cpu with the new target

2020-12-08 Thread Vincent Guittot
On Tue, 8 Dec 2020 at 16:35, Mel Gorman wrote: > > After select_idle_sibling, p->recent_used_cpu is set to the > new target. However on the next wakeup, prev will be the same as > recent_used_cpu unless the load balancer has moved the task since the last > wakeup. It still works, but is less

[PATCH 3/4] sched/fair: Do not replace recent_used_cpu with the new target

2020-12-08 Thread Mel Gorman
After select_idle_sibling, p->recent_used_cpu is set to the new target. However on the next wakeup, prev will be the same as recent_used_cpu unless the load balancer has moved the task since the last wakeup. It still works, but is less efficient than it can be after all the changes that went in