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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230814063428.4111206-3-zhangpeng362@huawei.com> X-Rspamd-Queue-Id: 6D45040005 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: jpbf8dw7oqs9uqbqeo5wkzrnbcbdx1zp X-HE-Tag: 1692168502-949253 X-HE-Meta: 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 TeGO1WYw /t69LYMHABZWFrSXCZvvXMkwRYdf6qH+8C7vyYCWRc/8DqZiQZc+8hz7zy3II5DF/ghVusX2t1MeAOxyKXMH/7gWzwl5K4/gzDT/W5AuwaNgu7ZV7+T5TRADzUcD/eBu0q/nQhGJYdTGTuykQ/sUDkWNh75hoDL3IZH8Rkvq17dIjvBtzbOXbfV9mxCJ+zo126P8Uo9rYA2fcDcjEBOCwH3smAw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 14-08-23 14:34:28, Peng Zhang wrote: > From: ZhangPeng > > If task is allocating a lot of memory and has been marked to be killed > first, then it gets the highest score (LONG_MAX). Therefore, there is no > need to continue to calculate the points of other tasks. Just terminate > the oom_evaluate_task() loop early, when the task with the highest score > is found. By doing this, we can get some performance gains in > select_bad_process(). The point of evaluating all tasks is that there might be pre-existing oom victim still being torn down. If you cut this short you might kill more tasks than necessary. So I do not think we want this patch. > To implement it, the return value of oom_evaluate_task() is modified. > When the task with the highest score is found (points == LONG_MAX), > oom_evaluate_task() will return 1 and the loop will terminate early. > > Signed-off-by: ZhangPeng > --- > mm/oom_kill.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > index 10f7826c4035..02d11ae043aa 100644 > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -346,6 +346,8 @@ static int oom_evaluate_task(struct task_struct *task, void *arg) > get_task_struct(task); > oc->chosen = task; > oc->chosen_points = points; > + if (points == LONG_MAX) > + return 1; > next: > return 0; > abort: > -- > 2.25.1 -- Michal Hocko SUSE Labs