Re: [PATCH 4/5] oom: don't kill random process

KOSAKI Motohiro
2011-05-24T08:49:44Z

(2011/05/24 17:46), Minchan Kim wrote:
> On Tue, May 24, 2011 at 10:53 AM, KOSAKI Motohiro
> <kosaki.motohiro@jp.fujitsu.com> wrote:
>>>> + /*
>>>> + * chosen_point==1 may be a sign that root privilege bonus is too
>>>> large
>>>> + * and we choose wrong task. Let's recalculate oom score without
>>>> the
>>>> + * dubious bonus.
>>>> + */
>>>> + if (protect_root&& (chosen_points == 1)) {
>>>> + protect_root = 0;
>>>> + goto retry;
>>>> + }
>>>
>>> The idea is good to me.
>>> But once we meet it, should we give up protecting root privileged
>>> processes?
>>> How about decaying bonus point?
>>
>> After applying my patch, unprivileged process never get score-1. (note,
>> mapping
>> anon pages naturally makes to increase nr_ptes)
>
> Hmm, If I understand your code correctly, unprivileged process can get
> a score 1 by 3% bonus.

3% bonus is for privileged process. :)

> So after all, we can get a chosen_point with 1.
> Why I get a chosen_point with 1 is as bonus is rather big, I think.
> So I would like to use small bonus than first iteration(ie, decay bonus).
>
>>
>> Then, decaying don't make any accuracy. Am I missing something?
>
> Maybe I miss something. :(
>
>
>
>