On 05/06/2013 01:39 PM, Alex Shi wrote: > On 05/06/2013 11:34 AM, Michael Wang wrote: >>>> @@ -3045,7 +3045,7 @@ static long effective_load(struct task_group *tg, >>>> int cpu, long wl, long wg) >>>> /* >>>> * w = rw_i + @wl >>>> */ >>>> - w = se->my_q->load.weight + wl; >>>> + w = se->my_q->tg_load_contrib + wl; >> I've tested the patch set, seems like the last patch caused big >> regression on pgbench: >> >> base patch 1~6 patch 1~7 >> | db_size | clients | tps | | tps | | tps | >> +---------+---------+-------+ +-------+ +-------+ >> | 22 MB | 32 | 43420 | | 53387 | | 41625 | >> >> I guess some magic thing happened in effective_load() while calculating >> group decay combined with load decay, what's your opinion? > > > thanks for testing, Michael! > > Maybe 2 fix worth to try. > > 1, change back the tg_weight in calc_tg_weight() to use tg_load_contrib not > direct load. > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 6f4f14b..c770f8d 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -1037,8 +1037,8 @@ static inline long calc_tg_weight(struct task_group > *tg, struct cfs_rq *cfs_rq) > * update_cfs_rq_load_contribution(). > */ > tg_weight = atomic64_read(&tg->load_avg); > - tg_weight -= cfs_rq->tg_load_contrib; > - tg_weight += cfs_rq->load.weight; > + //tg_weight -= cfs_rq->tg_load_contrib; > + //tg_weight += cfs_rq->load.weight; > > return tg_weight; > } > > 2, another try is follow the current calc_tg_weight, so remove the follow > change. > >>>> @@ -3045,7 +3045,7 @@ static long effective_load(struct task_group *tg, >>>> int cpu, long wl, long wg) >>>> /* >>>> * w = rw_i + @wl >>>> */ >>>> - w = se->my_q->load.weight + wl; >>>> + w = se->my_q->tg_load_contrib + wl; > > Would you like to try them?
Sure, I will take a try on both :) But actually I'm wondering whether it is necessary to change effective_load()? It is only severed for wake-affine and the whole stuff is still in the dark, if patch 1~6 already show good results, why don't we leave it there? So how about the situation on your box without the last patch? is the benefit still there? Regards, Michael Wang > > -- 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/
