Re: [PATCH v2] sched/pelt: Fix task util_est update filtering

2021-03-03 Thread Vincent Donnefort
On Mon, Mar 01, 2021 at 06:21:23PM +0100, Peter Zijlstra wrote: > On Mon, Mar 01, 2021 at 05:34:09PM +0100, Dietmar Eggemann wrote: > > On 26/02/2021 09:41, Peter Zijlstra wrote: > > > On Thu, Feb 25, 2021 at 04:58:20PM +, Vincent Donnefort wrote: > > >> +#define UTIL_EST_MARGIN

Re: [PATCH v2] sched/pelt: Fix task util_est update filtering

2021-03-01 Thread Peter Zijlstra
On Mon, Mar 01, 2021 at 05:34:09PM +0100, Dietmar Eggemann wrote: > On 26/02/2021 09:41, Peter Zijlstra wrote: > > On Thu, Feb 25, 2021 at 04:58:20PM +, Vincent Donnefort wrote: > >> +#define UTIL_EST_MARGIN (SCHED_CAPACITY_SCALE / 100) > >> + > >> /* > >> - * Check if a (signed) value is

Re: [PATCH v2] sched/pelt: Fix task util_est update filtering

2021-03-01 Thread Dietmar Eggemann
On 26/02/2021 09:41, Peter Zijlstra wrote: > On Thu, Feb 25, 2021 at 04:58:20PM +, Vincent Donnefort wrote: >> +#define UTIL_EST_MARGIN (SCHED_CAPACITY_SCALE / 100) >> + >> /* >> - * Check if a (signed) value is within a specified (unsigned) margin, >> + * Check if a (signed) value is within

Re: [PATCH v2] sched/pelt: Fix task util_est update filtering

2021-02-26 Thread Peter Zijlstra
On Thu, Feb 25, 2021 at 04:58:20PM +, Vincent Donnefort wrote: > +#define UTIL_EST_MARGIN (SCHED_CAPACITY_SCALE / 100) > + > /* > - * Check if a (signed) value is within a specified (unsigned) margin, > + * Check if a (signed) value is within the (unsigned) util_est margin, > * based on the

Re: [PATCH v2] sched/pelt: Fix task util_est update filtering

2021-02-25 Thread Vincent Guittot
On Thu, 25 Feb 2021 at 17:58, Vincent Donnefort wrote: > > Being called for each dequeue, util_est reduces the number of its updates > by filtering out when the EWMA signal is different from the task util_avg > by less than 1%. It is a problem for a sudden util_avg ramp-up. Due to the > decay

[PATCH v2] sched/pelt: Fix task util_est update filtering

2021-02-25 Thread Vincent Donnefort
Being called for each dequeue, util_est reduces the number of its updates by filtering out when the EWMA signal is different from the task util_avg by less than 1%. It is a problem for a sudden util_avg ramp-up. Due to the decay from a previous high util_avg, EWMA might now be close enough to the