[PATCHES/RFC] Re: A concern about overflow ring buffer mode

From: Arnaldo Carvalho de Melo
Date: Mon Oct 29 2018 - 09:03:38 EST


Em Fri, Oct 26, 2018 at 04:11:51PM -0400, Liang, Kan escreveu:
> On 10/26/2018 3:24 PM, Arnaldo Carvalho de Melo wrote:
> > Em Fri, Oct 26, 2018 at 03:16:29PM -0400, Liang, Kan escreveu:
> > > On 10/26/2018 3:12 PM, Arnaldo Carvalho de Melo wrote:
> > > > Em Fri, Oct 26, 2018 at 03:07:40PM -0400, Liang, Kan escreveu:
> > > > > On 10/26/2018 3:02 PM, Arnaldo Carvalho de Melo wrote:
> > > > I checked and both have the same result. But I still think there is
> > > > value in having the shorter form, ok?

> > > Sure.

> > Ok.

> > I think that we should default back to --no-overwrite till we get this
> > sorted out, as the effect is easily noticeable, as David reported and I
> > reproduced, when doing kernel builds.

> It is mainly for performance reason to switch to overwrite mode. The impact
> was very small when I did my test. But now the effect is easily noticeable
> in other tests. Yes, I agree. We may change it back to non-overwrite mode
> until the issue is addressed.

So, I have these two patches in my perf/core branch, with Fixes tags
that will make them get to the stable kernels, ok?