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> - move cfs_rq->last_update_tg_load_avg before cfs_rq->tg_load_avg_contrib; > - add Vincent's reviewed-by tag. > > RFC v2: > Nitin Tekchandani noticed some scheduler functions have high cost > according to perf/cycles while running postgres_sysbench workload. > I perf/annotated the high cost functions: update_cfs_group() and > update_load_avg() and found the costs were ~90% due to accessing to > tg->load_avg. This series is an attempt to reduce the overhead of > the two functions. > > Thanks to Vincent's suggestion from v1, this revision used a simpler way > to solve the overhead problem by limiting updates to tg->load_avg to at > most once per ms. Benchmark shows that it has good results and with the > rate limit in place, other optimizations in v1 don't improve performance > further so they are dropped from this revision. > I have tested this series alongside Mathieu's changes. You can find the report here: https://lore.kernel.org/all/f6dc1652-bc39-0b12-4b6b-29a2f9cd8484@amd.com/ Tested-by: Swapnil Sapkal > Aaron Lu (1): > sched/fair: ratelimit update to tg->load_avg > > kernel/sched/fair.c | 13 ++++++++++++- > kernel/sched/sched.h | 1 + > 2 files changed, 13 insertions(+), 1 deletion(-) > -- Thanks and Regards, Swapnil