Re: [RFCv3 PATCH 47/48] sched: Enable active migration for cpus of lower capacity

From: Peter Zijlstra
Date: Tue Mar 24 2015 - 12:02:58 EST


On Wed, Feb 04, 2015 at 06:31:24PM +0000, Morten Rasmussen wrote:
> Add an extra criteria to need_active_balance() to kick off active load
> balance if the source cpu is overutilized and has lower capacity than
> the destination cpus.
>
> cc: Ingo Molnar <mingo@xxxxxxxxxx>
> cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
>
> Signed-off-by: Morten Rasmussen <morten.rasmussen@xxxxxxx>
> ---
> kernel/sched/fair.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 92fd1d8..1c248f8 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -7379,6 +7379,13 @@ static int need_active_balance(struct lb_env *env)
> return 1;
> }
>
> + if ((capacity_of(env->src_cpu) < capacity_of(env->dst_cpu)) &&
> + env->src_rq->cfs.h_nr_running == 1 &&
> + cpu_overutilized(env->src_cpu, env->sd) &&
> + !cpu_overutilized(env->dst_cpu, env->sd)) {
> + return 1;
> + }

Ah, see does this want to get squashed into the previuos patch? Together
they seem to make more sense.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/