Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-15 Thread Vincent Guittot
Hi Dietmar, On 15 April 2018 at 13:56, Dietmar Eggemann wrote: > On 03/16/2018 12:25 PM, Vincent Guittot wrote: > > [...] > > >> For a 15 seconds long test on a hikey 6220 (octo core cortex A53 >> platfrom), >> the cpufreq statistics outputs (stats are reset just before

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-15 Thread Vincent Guittot
Hi Dietmar, On 15 April 2018 at 13:56, Dietmar Eggemann wrote: > On 03/16/2018 12:25 PM, Vincent Guittot wrote: > > [...] > > >> For a 15 seconds long test on a hikey 6220 (octo core cortex A53 >> platfrom), >> the cpufreq statistics outputs (stats are reset just before the test) : >> $ cat

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-15 Thread Dietmar Eggemann
On 03/16/2018 12:25 PM, Vincent Guittot wrote: [...] For a 15 seconds long test on a hikey 6220 (octo core cortex A53 platfrom), the cpufreq statistics outputs (stats are reset just before the test) : $ cat /sys/devices/system/cpu/cpufreq/policy0/stats/total_trans without patchset : 1230 with

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-15 Thread Dietmar Eggemann
On 03/16/2018 12:25 PM, Vincent Guittot wrote: [...] For a 15 seconds long test on a hikey 6220 (octo core cortex A53 platfrom), the cpufreq statistics outputs (stats are reset just before the test) : $ cat /sys/devices/system/cpu/cpufreq/policy0/stats/total_trans without patchset : 1230 with

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-14 Thread Vincent Guittot
On 14 April 2018 at 12:07, Peter Zijlstra wrote: > > > What I don't see in this patch-set is removal of the current rt_avg > stuff. This RT load tracking doesn't replace current rt_avg because they are not using same period and providing same function current rt_avg uses

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-14 Thread Vincent Guittot
On 14 April 2018 at 12:07, Peter Zijlstra wrote: > > > What I don't see in this patch-set is removal of the current rt_avg > stuff. This RT load tracking doesn't replace current rt_avg because they are not using same period and providing same function current rt_avg uses sysctl_sched_time_avg to

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-14 Thread Peter Zijlstra
What I don't see in this patch-set is removal of the current rt_avg stuff. And I didn't look closely enough; but are the root cfs and rt pelt windows aligned? They really should be; otherwise you can't combine them sanely.

Re: [PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-04-14 Thread Peter Zijlstra
What I don't see in this patch-set is removal of the current rt_avg stuff. And I didn't look closely enough; but are the root cfs and rt pelt windows aligned? They really should be; otherwise you can't combine them sanely.

[PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-03-16 Thread Vincent Guittot
When both cfs and rt tasks compete to run on a CPU, we can see some frequency drops with schedutil governor. In such case, the cfs_rq's utilization doesn't reflect anymore the utilization of cfs tasks but only the remaining part that is not used by rt tasks. We should monitor the stolen

[PATCH 0/4 v4] sched/rt: track rt rq utilization

2018-03-16 Thread Vincent Guittot
When both cfs and rt tasks compete to run on a CPU, we can see some frequency drops with schedutil governor. In such case, the cfs_rq's utilization doesn't reflect anymore the utilization of cfs tasks but only the remaining part that is not used by rt tasks. We should monitor the stolen