On Tue, 27 Sep, at 02:48:31PM, Dietmar Eggemann wrote: > > I think Matt is talking about the fact that the cfs->runnable_load_avg > value is 0 once the hackbench task is initially dequeued. Yes.
> Without this patch the value of se->avg.load_avg (e.g. both times 1002) > is exactly the same when we add it to cfs_rq->runnable_load_avg in > enqueue_entity_load_avg() and when we subtract it in > dequeue_entity_load_avg(). That's because the initial runtime is short > (~250us on my hikey board). > > With this patch we add 1024 and subtract ~1002 which lets > cfs_rq->runnable_load_avg still have a small positive value. This > favours that for the next hackbench task another cpu will be chosen in > (load-based) fork-balance. Bingo, that's exactly it. Sorry if i was unclear.
