Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932960Ab3FQMRv (ORCPT ); Mon, 17 Jun 2013 08:17:51 -0400 Received: from mail-lb0-f176.google.com ([209.85.217.176]:51795 "EHLO mail-lb0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932727Ab3FQMRt (ORCPT ); Mon, 17 Jun 2013 08:17:49 -0400 MIME-Version: 1.0 In-Reply-To: References: <1370589652-24549-1-git-send-email-alex.shi@intel.com> <1370589652-24549-7-git-send-email-alex.shi@intel.com> From: Paul Turner Date: Mon, 17 Jun 2013 05:17:17 -0700 Message-ID: Subject: Re: [patch v8 6/9] sched: compute runnable load avg in cpu_load and cpu_avg_load_per_task To: Alex Shi Cc: Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Andrew Morton , Borislav Petkov , Namhyung Kim , Mike Galbraith , Morten Rasmussen , Vincent Guittot , Preeti U Murthy , Viresh Kumar , LKML , Mel Gorman , Rik van Riel , Michael Wang , Jason Low , Changlong Xie , sgruszka@redhat.com, =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3879 Lines: 112 On Mon, Jun 17, 2013 at 3:51 AM, Paul Turner wrote: > On Fri, Jun 7, 2013 at 12:20 AM, Alex Shi wrote: >> They are the base values in load balance, update them with rq runnable >> load average, then the load balance will consider runnable load avg >> naturally. >> >> We also try to include the blocked_load_avg as cpu load in balancing, >> but that cause kbuild performance drop 6% on every Intel machine, and >> aim7/oltp drop on some of 4 CPU sockets machines. >> > > This looks fine. > > Did you try including blocked_load_avg in only get_rq_runnable_load() > [ and not weighted_cpuload() which is called by new-idle ]? Looking at this more this feels less correct since you're taking averages of averages. This was previously discussed at: https://lkml.org/lkml/2013/5/6/109 And you later replied suggesting this didn't seem to hurt; what's the current status there? > >> Signed-off-by: Alex Shi >> --- >> kernel/sched/fair.c | 5 +++-- >> kernel/sched/proc.c | 17 +++++++++++++++-- >> 2 files changed, 18 insertions(+), 4 deletions(-) >> >> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >> index 42c7be0..eadd2e7 100644 >> --- a/kernel/sched/fair.c >> +++ b/kernel/sched/fair.c >> @@ -2962,7 +2962,7 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) >> /* Used instead of source_load when we know the type == 0 */ >> static unsigned long weighted_cpuload(const int cpu) >> { >> - return cpu_rq(cpu)->load.weight; >> + return cpu_rq(cpu)->cfs.runnable_load_avg; >> } >> >> /* >> @@ -3007,9 +3007,10 @@ static unsigned long cpu_avg_load_per_task(int cpu) >> { >> struct rq *rq = cpu_rq(cpu); >> unsigned long nr_running = ACCESS_ONCE(rq->nr_running); >> + unsigned long load_avg = rq->cfs.runnable_load_avg; >> >> if (nr_running) >> - return rq->load.weight / nr_running; >> + return load_avg / nr_running; >> >> return 0; >> } >> diff --git a/kernel/sched/proc.c b/kernel/sched/proc.c >> index bb3a6a0..ce5cd48 100644 >> --- a/kernel/sched/proc.c >> +++ b/kernel/sched/proc.c >> @@ -501,6 +501,18 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load, >> sched_avg_update(this_rq); >> } >> >> +#ifdef CONFIG_SMP >> +unsigned long get_rq_runnable_load(struct rq *rq) >> +{ >> + return rq->cfs.runnable_load_avg; >> +} >> +#else >> +unsigned long get_rq_runnable_load(struct rq *rq) >> +{ >> + return rq->load.weight; >> +} >> +#endif >> + >> #ifdef CONFIG_NO_HZ_COMMON >> /* >> * There is no sane way to deal with nohz on smp when using jiffies because the >> @@ -522,7 +534,7 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load, >> void update_idle_cpu_load(struct rq *this_rq) >> { >> unsigned long curr_jiffies = ACCESS_ONCE(jiffies); >> - unsigned long load = this_rq->load.weight; >> + unsigned long load = get_rq_runnable_load(this_rq); >> unsigned long pending_updates; >> >> /* >> @@ -568,11 +580,12 @@ void update_cpu_load_nohz(void) >> */ >> void update_cpu_load_active(struct rq *this_rq) >> { >> + unsigned long load = get_rq_runnable_load(this_rq); >> /* >> * See the mess around update_idle_cpu_load() / update_cpu_load_nohz(). >> */ >> this_rq->last_load_update_tick = jiffies; >> - __update_cpu_load(this_rq, this_rq->load.weight, 1); >> + __update_cpu_load(this_rq, load, 1); >> >> calc_load_account_active(this_rq); >> } >> -- >> 1.7.12 >> -- 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/