| Message ID | 1412684017-16595-5-git-send-email-vincent.guittot@linaro.org |
|---|---|
| State | New |
| Headers | show |
Vincent Guittot <vincent.guittot@linaro.org> writes: > From: Morten Rasmussen <morten.rasmussen@arm.com> > > Adds usage contribution tracking for group entities. Unlike > se->avg.load_avg_contrib, se->avg.utilization_avg_contrib for group > entities is the sum of se->avg.utilization_avg_contrib for all entities on the > group runqueue. It is _not_ influenced in any way by the task group > h_load. Hence it is representing the actual cpu usage of the group, not > its intended load contribution which may differ significantly from the > utilization on lightly utilized systems. Just noting that this version also has usage disappear immediately when a task blocks, although it does what you probably want on migration. Also, group-ses don't ever use their running_avg_sum so it's kinda a waste, but I'm not sure it's worth doing anything about. > > cc: Paul Turner <pjt@google.com> > cc: Ben Segall <bsegall@google.com> > > Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com> > --- > kernel/sched/debug.c | 3 +++ > kernel/sched/fair.c | 5 +++++ > 2 files changed, 8 insertions(+) > > diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c > index e0fbc0f..efb47ed 100644 > --- a/kernel/sched/debug.c > +++ b/kernel/sched/debug.c > @@ -94,8 +94,10 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group > P(se->load.weight); > #ifdef CONFIG_SMP > P(se->avg.runnable_avg_sum); > + P(se->avg.running_avg_sum); > P(se->avg.avg_period); > P(se->avg.load_avg_contrib); > + P(se->avg.utilization_avg_contrib); > P(se->avg.decay_count); > #endif > #undef PN > @@ -633,6 +635,7 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m) > P(se.avg.running_avg_sum); > P(se.avg.avg_period); > P(se.avg.load_avg_contrib); > + P(se.avg.utilization_avg_contrib); > P(se.avg.decay_count); > #endif > P(policy); > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index d6de526..d3e9067 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -2381,6 +2381,8 @@ static inline u64 __synchronize_entity_decay(struct sched_entity *se) > return 0; > > se->avg.load_avg_contrib = decay_load(se->avg.load_avg_contrib, decays); > + se->avg.utilization_avg_contrib = > + decay_load(se->avg.utilization_avg_contrib, decays); > se->avg.decay_count = 0; > > return decays; > @@ -2525,6 +2527,9 @@ static long __update_entity_utilization_avg_contrib(struct sched_entity *se) > > if (entity_is_task(se)) > __update_task_entity_utilization(se); > + else > + se->avg.utilization_avg_contrib = > + group_cfs_rq(se)->utilization_load_avg; > > return se->avg.utilization_avg_contrib - old_contrib; > } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On 7 October 2014 22:15, <bsegall@google.com> wrote: > Vincent Guittot <vincent.guittot@linaro.org> writes: > >> From: Morten Rasmussen <morten.rasmussen@arm.com> >> >> Adds usage contribution tracking for group entities. Unlike >> se->avg.load_avg_contrib, se->avg.utilization_avg_contrib for group >> entities is the sum of se->avg.utilization_avg_contrib for all entities on the >> group runqueue. It is _not_ influenced in any way by the task group >> h_load. Hence it is representing the actual cpu usage of the group, not >> its intended load contribution which may differ significantly from the >> utilization on lightly utilized systems. > > > Just noting that this version also has usage disappear immediately when > a task blocks, although it does what you probably want on migration. Yes. For this patchset, we prefer to stay aligned with current implementation which only take into account runnable tasks in order cap the change of the behavior. IMHO, the use of blocked task in utilization_avg_contrib should be part of a dedicated patchset with dedicated non regression test > > Also, group-ses don't ever use their running_avg_sum so it's kinda a > waste, but I'm not sure it's worth doing anything about. > >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On Tue, Oct 07, 2014 at 09:15:39PM +0100, bsegall@google.com wrote: > Vincent Guittot <vincent.guittot@linaro.org> writes: > > > From: Morten Rasmussen <morten.rasmussen@arm.com> > > > > Adds usage contribution tracking for group entities. Unlike > > se->avg.load_avg_contrib, se->avg.utilization_avg_contrib for group > > entities is the sum of se->avg.utilization_avg_contrib for all entities on the > > group runqueue. It is _not_ influenced in any way by the task group > > h_load. Hence it is representing the actual cpu usage of the group, not > > its intended load contribution which may differ significantly from the > > utilization on lightly utilized systems. > > > Just noting that this version also has usage disappear immediately when > a task blocks, although it does what you probably want on migration. Yes, as it was discussed at Ksummit, we should include blocked usage. It gives a much more stable metric. > Also, group-ses don't ever use their running_avg_sum so it's kinda a > waste, but I'm not sure it's worth doing anything about. Yeah, but since we still have to maintain runnable_avg_sum for group-ses it isn't much that can be saved I think. Maybe avoid calling update_entity_load_avg() from set_next_entity() for group-ses, but I'm not sure how much it helps. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index e0fbc0f..efb47ed 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -94,8 +94,10 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group P(se->load.weight); #ifdef CONFIG_SMP P(se->avg.runnable_avg_sum); + P(se->avg.running_avg_sum); P(se->avg.avg_period); P(se->avg.load_avg_contrib); + P(se->avg.utilization_avg_contrib); P(se->avg.decay_count); #endif #undef PN @@ -633,6 +635,7 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m) P(se.avg.running_avg_sum); P(se.avg.avg_period); P(se.avg.load_avg_contrib); + P(se.avg.utilization_avg_contrib); P(se.avg.decay_count); #endif P(policy); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d6de526..d3e9067 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2381,6 +2381,8 @@ static inline u64 __synchronize_entity_decay(struct sched_entity *se) return 0; se->avg.load_avg_contrib = decay_load(se->avg.load_avg_contrib, decays); + se->avg.utilization_avg_contrib = + decay_load(se->avg.utilization_avg_contrib, decays); se->avg.decay_count = 0; return decays; @@ -2525,6 +2527,9 @@ static long __update_entity_utilization_avg_contrib(struct sched_entity *se) if (entity_is_task(se)) __update_task_entity_utilization(se); + else + se->avg.utilization_avg_contrib = + group_cfs_rq(se)->utilization_load_avg; return se->avg.utilization_avg_contrib - old_contrib; }