Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220702045254.22922-1-vincent.guittot@linaro.org> <e830e6eb-6606-74f1-c356-cb61c6f46e99@huawei.com>
In-Reply-To: <e830e6eb-6606-74f1-c356-cb61c6f46e99@huawei.com>
From:   Vincent Guittot <vincent.guittot@linaro.org>
Date:   Thu, 7 Jul 2022 08:42:32 +0200
Message-ID: <CAKfTPtA1fARYDTapz3LL=-XOhJ5=TAj8YP0RP6ANit_67XhE0g@mail.gmail.com>
Subject: Re: [PATCH] sched/fair: fix case with reduced capacity CPU
To:     Zhang Qiao <zhangqiao22@huawei.com>
Cc:     mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com,
        mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com,
        linux-kernel@vger.kernel.org, david.chen@nutanix.com
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Tue, 5 Jul 2022 at 10:23, Zhang Qiao <zhangqiao22@huawei.com> wrote:
>
>
>
> =E5=9C=A8 2022/7/2 12:52, Vincent Guittot =E5=86=99=E9=81=93:
> > The capacity of the CPU available for CFS tasks can be reduced because =
of
> > other activities running on the latter. In such case, it's worth trying=
 to
> > move CFS tasks on a CPU with more available capacity.
> >
> > The rework of the load balance has filterd the case when the CPU is
> > classified to be fully busy but its capacity is reduced.
> >
> > Check if CPU's capacity is reduced while gathering load balance statist=
ics
> > and classify it group_misfit_task instead of group_fully_busy so we can
> > try to move the load on another CPU.
> >
> > Reported-by: David Chen <david.chen@nutanix.com>
> > Reported-by: Zhang Qiao <zhangqiao22@huawei.com>
> > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
> > ---
> >
> > David, Zhang,
> >
> > I haven't put your tested-by because I have reworked and cleaned the pa=
tch to
> > cover more cases.
> >
> > Could you run some tests with this version ?
>
> I tested with this version, it is ok.
>
> Tested-by: Zhang Qiao <zhangqiao22@huawei.com>

Thanks

>
> Thanks
>
> >

> >