Re: [patch v4 11/18] sched: log the cpu utilization at rq
On 02/12/2013 06:39 PM, Peter Zijlstra wrote: > On Thu, 2013-01-24 at 11:06 +0800, Alex Shi wrote: >> >> The cpu's utilization is to measure how busy is the cpu. >> util = cpu_rq(cpu)->avg.runnable_avg_sum >> / cpu_rq(cpu)->avg.runnable_avg_period; >> >> Since the util is no more than 1, we use its percentage value in later >> caculations. And set the the FULL_UTIL as 100%. >> >> In later power aware scheduling, we are sensitive for how busy of the >> cpu, not how much weight of its load. As to power consuming, it is more >> related with cpu busy time, not the load weight. > > I think we can make that argument in general; that is irrespective of > the actual policy. We simply never had anything better to go with. > > So please clarify why you think this only applies to power aware > scheduling. Um, the rq->util is a general argument. It can be used on any other places if needed, not power aware scheduling specific. > -- Thanks Alex -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [patch v4 11/18] sched: log the cpu utilization at rq
On 02/12/2013 06:39 PM, Peter Zijlstra wrote: On Thu, 2013-01-24 at 11:06 +0800, Alex Shi wrote: The cpu's utilization is to measure how busy is the cpu. util = cpu_rq(cpu)-avg.runnable_avg_sum / cpu_rq(cpu)-avg.runnable_avg_period; Since the util is no more than 1, we use its percentage value in later caculations. And set the the FULL_UTIL as 100%. In later power aware scheduling, we are sensitive for how busy of the cpu, not how much weight of its load. As to power consuming, it is more related with cpu busy time, not the load weight. I think we can make that argument in general; that is irrespective of the actual policy. We simply never had anything better to go with. So please clarify why you think this only applies to power aware scheduling. Um, the rq-util is a general argument. It can be used on any other places if needed, not power aware scheduling specific. -- Thanks Alex -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [patch v4 11/18] sched: log the cpu utilization at rq
On Thu, 2013-01-24 at 11:06 +0800, Alex Shi wrote: > > The cpu's utilization is to measure how busy is the cpu. > util = cpu_rq(cpu)->avg.runnable_avg_sum > / cpu_rq(cpu)->avg.runnable_avg_period; > > Since the util is no more than 1, we use its percentage value in later > caculations. And set the the FULL_UTIL as 100%. > > In later power aware scheduling, we are sensitive for how busy of the > cpu, not how much weight of its load. As to power consuming, it is more > related with cpu busy time, not the load weight. I think we can make that argument in general; that is irrespective of the actual policy. We simply never had anything better to go with. So please clarify why you think this only applies to power aware scheduling. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [patch v4 11/18] sched: log the cpu utilization at rq
On Thu, 2013-01-24 at 11:06 +0800, Alex Shi wrote: The cpu's utilization is to measure how busy is the cpu. util = cpu_rq(cpu)-avg.runnable_avg_sum / cpu_rq(cpu)-avg.runnable_avg_period; Since the util is no more than 1, we use its percentage value in later caculations. And set the the FULL_UTIL as 100%. In later power aware scheduling, we are sensitive for how busy of the cpu, not how much weight of its load. As to power consuming, it is more related with cpu busy time, not the load weight. I think we can make that argument in general; that is irrespective of the actual policy. We simply never had anything better to go with. So please clarify why you think this only applies to power aware scheduling. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[patch v4 11/18] sched: log the cpu utilization at rq
The cpu's utilization is to measure how busy is the cpu. util = cpu_rq(cpu)->avg.runnable_avg_sum / cpu_rq(cpu)->avg.runnable_avg_period; Since the util is no more than 1, we use its percentage value in later caculations. And set the the FULL_UTIL as 100%. In later power aware scheduling, we are sensitive for how busy of the cpu, not how much weight of its load. As to power consuming, it is more related with cpu busy time, not the load weight. Signed-off-by: Alex Shi --- kernel/sched/debug.c | 1 + kernel/sched/fair.c | 4 kernel/sched/sched.h | 4 3 files changed, 9 insertions(+) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 2cd3c1b..e4035f7 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -318,6 +318,7 @@ do { \ P(ttwu_count); P(ttwu_local); + P(util); #undef P #undef P64 diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 947542f..20363fb 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1495,8 +1495,12 @@ static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq, int force_update) static inline void update_rq_runnable_avg(struct rq *rq, int runnable) { + u32 period; __update_entity_runnable_avg(rq->clock_task, >avg, runnable); __update_tg_runnable_avg(>avg, >cfs); + + period = rq->avg.runnable_avg_period ? rq->avg.runnable_avg_period : 1; + rq->util = rq->avg.runnable_avg_sum * 100 / period; } /* Add the load generated by se into cfs_rq's child load-average */ diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 66b08a1..fa8bdb9 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -350,6 +350,9 @@ extern struct root_domain def_root_domain; #endif /* CONFIG_SMP */ +/* the percentage full cpu utilization */ +#define FULL_UTIL 100 + /* * This is the main, per-CPU runqueue data structure. * @@ -481,6 +484,7 @@ struct rq { #endif struct sched_avg avg; + unsigned int util; }; static inline int cpu_of(struct rq *rq) -- 1.7.12 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[patch v4 11/18] sched: log the cpu utilization at rq
The cpu's utilization is to measure how busy is the cpu. util = cpu_rq(cpu)-avg.runnable_avg_sum / cpu_rq(cpu)-avg.runnable_avg_period; Since the util is no more than 1, we use its percentage value in later caculations. And set the the FULL_UTIL as 100%. In later power aware scheduling, we are sensitive for how busy of the cpu, not how much weight of its load. As to power consuming, it is more related with cpu busy time, not the load weight. Signed-off-by: Alex Shi alex@intel.com --- kernel/sched/debug.c | 1 + kernel/sched/fair.c | 4 kernel/sched/sched.h | 4 3 files changed, 9 insertions(+) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 2cd3c1b..e4035f7 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -318,6 +318,7 @@ do { \ P(ttwu_count); P(ttwu_local); + P(util); #undef P #undef P64 diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 947542f..20363fb 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1495,8 +1495,12 @@ static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq, int force_update) static inline void update_rq_runnable_avg(struct rq *rq, int runnable) { + u32 period; __update_entity_runnable_avg(rq-clock_task, rq-avg, runnable); __update_tg_runnable_avg(rq-avg, rq-cfs); + + period = rq-avg.runnable_avg_period ? rq-avg.runnable_avg_period : 1; + rq-util = rq-avg.runnable_avg_sum * 100 / period; } /* Add the load generated by se into cfs_rq's child load-average */ diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 66b08a1..fa8bdb9 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -350,6 +350,9 @@ extern struct root_domain def_root_domain; #endif /* CONFIG_SMP */ +/* the percentage full cpu utilization */ +#define FULL_UTIL 100 + /* * This is the main, per-CPU runqueue data structure. * @@ -481,6 +484,7 @@ struct rq { #endif struct sched_avg avg; + unsigned int util; }; static inline int cpu_of(struct rq *rq) -- 1.7.12 -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/