Re: [PATCH v2] sched/fair: Make PELT signal more accurate

2017-08-19 Thread Joel Fernandes
Hi Mike, On Sat, Aug 19, 2017 at 11:00 PM, Mike Galbraith wrote: > On Sat, 2017-08-19 at 10:58 -0700, Joel Fernandes wrote: >> >> > Ok, I gotta ask: In order to fix what? What exactly does the small >> > but existent overhead increase buy us other than an ever so slightly >> > different chart?

Re: [PATCH v2] sched/fair: Make PELT signal more accurate

2017-08-19 Thread Mike Galbraith
On Sat, 2017-08-19 at 10:58 -0700, Joel Fernandes wrote: > > > Ok, I gotta ask: In order to fix what? What exactly does the small > > but existent overhead increase buy us other than an ever so slightly > > different chart? What is your motivation to care about a microscopic > > change in signa

Re: [PATCH v2] sched/fair: Make PELT signal more accurate

2017-08-19 Thread Joel Fernandes
Hi Mike, On Fri, Aug 18, 2017 at 9:57 PM, Mike Galbraith wrote: > On Fri, 2017-08-18 at 16:50 -0700, Joel Fernandes wrote: >> The PELT signal (sa->load_avg and sa->util_avg) are not updated if the amount >> accumulated during a single update doesn't cross a period boundary. This is >> fine in cas

Re: [PATCH v2] sched/fair: Make PELT signal more accurate

2017-08-18 Thread Mike Galbraith
On Fri, 2017-08-18 at 16:50 -0700, Joel Fernandes wrote: > The PELT signal (sa->load_avg and sa->util_avg) are not updated if the amount > accumulated during a single update doesn't cross a period boundary. This is > fine in cases where the amount accrued is much smaller than the size of a > single

[PATCH v2] sched/fair: Make PELT signal more accurate

2017-08-18 Thread Joel Fernandes
The PELT signal (sa->load_avg and sa->util_avg) are not updated if the amount accumulated during a single update doesn't cross a period boundary. This is fine in cases where the amount accrued is much smaller than the size of a single PELT window (1ms) however if the amount accrued is high then the