Re: [PATCH] mm,oom: add tracepoints for oom reaper-related events

From: Tetsuo Handa
Date: Tue May 30 2017 - 09:17:35 EST


Michal Hocko wrote:
> On Tue 30-05-17 13:05:32, Roman Gushchin wrote:
> > Add tracepoints to simplify the debugging of the oom reaper code.
> >
> > Trace the following events:
> > 1) a process is marked as an oom victim,
> > 2) a process is added to the oom reaper list,
> > 3) the oom reaper starts reaping process's mm,
> > 4) the oom reaper finished reaping,
> > 5) the oom reaper skips reaping.
>
> I am not against but could you explain why the current printks are not
> sufficient? We do not have any explicit printk for the 2) and 3) but
> are those really necessary?
>
> In other words could you describe the situation when you found these
> tracepoints more useful than what the kernel log offers already?

Guessing from "to simplify the debugging of the oom reaper code",
Roman is facing some unknown bugs or problems?