Re: mm->oom_disable_count is broken

Oleg Nesterov
2011-08-29T18:42:06Z

On 08/01, KOSAKI Motohiro wrote:
>
> > And this reminds me. mm->oom_disable_count looks absolutely broken.
> > IIRC, I already complained but nobody replied.
> >
> > [...snip...]
>
> IIRC, I did pointed out this issue. But nobody replied.
> I think ->oom_disable_count is currently broken. but now I have no time to
> audit this stuff. So, I'd suggest to revert this code if nobody don't fix it.

I tend to agree, of course we can fix oom_disable_count but I don't
really understand why do we want it.

David, could you please explain? I mean, CLONE_VM (without CLONE_THREAD)
is not that common, I think. Does this counter really help in practice?

And. personally I dislike it because ->oom_disable_count is just another
proof that ->oom_score_adj should be in ->mm, not per-process. IIRC,
you already explained me why we can't do this, but - sorry - I forgot.
May be something with vfork... Could you explain this again?

Oleg.