Re: additional oom-killer tuneable worth submitting?

Peter Zijlstra
2006-12-07T19:21:50Z

On Thu, 2006-12-07 at 12:30 -0600, Chris Friesen wrote:
> The kernel currently has a way to adjust the oom-killer score via
> /proc/<pid>/oomadj.
>
> However, to adjust this effectively requires knowledge of the scores of
> all the other processes on the system.
>
> I'd like to float an idea (which we've implemented and been using for
> some time) where the semantics are slightly different:
>
> We add a new "oom_thresh" member to the task struct.
> We introduce a new proc entry "/proc/<pid>/oomthresh" to control it.
>
> The "oom-thresh" value maps to the max expected memory consumption for
> that process. As long as a process uses less memory than the specified
> threshold, then it is immune to the oom-killer.

You would need to specify the measure of memory used by your process;
see the (still not resolved) RSS debate.

> On an embedded platform this allows the designer to engineer the system
> and protect critical apps based on their expected memory consumption.
> If one of those apps goes crazy and starts chewing additional memory
> then it becomes vulnerable to the oom killer while the other apps remain
> protected.
>
> If a patch for the above feature was submitted, would there be any
> chance of getting it included? Maybe controlled by a config option?