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Date:   Fri, 20 May 2022 13:00:05 -0400
From:   Kent Overstreet <kent.overstreet@gmail.com>
To:     Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc:     Roman Gushchin <roman.gushchin@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        Dave Chinner <dchinner@redhat.com>,
        linux-kernel@vger.kernel.org, Hillf Danton <hdanton@sina.com>
Subject: Re: [PATCH v3 2/6] mm: shrinkers: introduce debugfs interface for
 memory shrinkers
Message-ID: <20220520170005.a3dlxk6a2qbrjdoq@moria.home.lan>
References: <20220509183820.573666-1-roman.gushchin@linux.dev>
 <20220509183820.573666-3-roman.gushchin@linux.dev>
 <d938e52e-3704-d095-cafe-a6218701896a@wanadoo.fr>
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On Fri, May 20, 2022 at 06:58:12PM +0200, Christophe JAILLET wrote:
> Le 09/05/2022 à 20:38, Roman Gushchin a écrit :
> > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> > index 3fd7a2e9eaf1..5fa65a649798 100644
> > --- a/lib/Kconfig.debug
> > +++ b/lib/Kconfig.debug
> > @@ -733,6 +733,15 @@ config SLUB_STATS
> >   	  out which slabs are relevant to a particular load.
> >   	  Try running: slabinfo -DA
> > +config SHRINKER_DEBUG
> > +	default y
> 
> The previous version of the serie had default 'n'.
> Is it intentional to have it now activated by default? It looked more like a
> tuning functionality when fine grained mangement of shrinker is needed.

I think having this on by default if you've already enabled debugfs is smart -
it doesn't add runtime overhead, just a bit of code, and things that make the
system more observable are great to have on by default.