Re: [PATCH v2] mm: emit tracepoint when RSS changes by threshold

From: Joel Fernandes
Date: Wed Sep 04 2019 - 01:15:53 EST


On Tue, Sep 03, 2019 at 09:51:20PM -0700, Daniel Colascione wrote:
> On Tue, Sep 3, 2019 at 9:45 PM Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote:
> >
> > On Tue, Sep 3, 2019 at 1:09 PM Joel Fernandes (Google)
> > <joel@xxxxxxxxxxxxxxxxx> wrote:
> > >
> > > Useful to track how RSS is changing per TGID to detect spikes in RSS and
> > > memory hogs. Several Android teams have been using this patch in various
> > > kernel trees for half a year now. Many reported to me it is really
> > > useful so I'm posting it upstream.
>
> It's also worth being able to turn off the per-task memory counter
> caching, otherwise you'll have two levels of batching before the
> counter gets updated, IIUC.

I prefer to keep split RSS accounting turned on if it is available. I think
discussing split RSS accounting is a bit out of scope of this patch as well.
Any improvements on that front can be a follow-up.

Curious, has split RSS accounting shown you any issue with this patch?

thanks,

- Joel