Re: [RFC][PATCH] oom: Be less verbose if the oom_control event fd has listeners

Richard Weinberger
2014-06-05T15:55:54Z

Am 05.06.2014 17:00, schrieb Michal Hocko:
> On Thu 05-06-14 16:00:41, Richard Weinberger wrote:
>> Don't spam the kernel logs if the oom_control event fd has listeners.
>> In this case there is no need to print that much lines as user space
>> will anyway notice that the memory cgroup has reached its limit.
>
> But how do you debug why it is reaching the limit and why a particular
> process has been killed?

In my case it's always because customer's Java application gone nuts.
So I don't really have to debug a lot. ;-)
But I can understand your point.

> If we are printing too much then OK, let's remove those parts which are
> not that useful but hiding information which tells us more about the oom
> decision doesn't sound right to me.

What about adding a sysctl like "vm.oom_verbose"?
By default it would be 1.
If set to 0 the full OOM information is only printed out if nobody listens
to the event fd.

Thanks,
//richard