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Date:   Wed, 6 Dec 2023 14:13:49 -0500
From:   Kent Overstreet <kent.overstreet@linux.dev>
To:     Dave Chinner <david@fromorbit.com>
Cc:     Roman Gushchin <roman.gushchin@linux.dev>,
        Qi Zheng <zhengqi.arch@bytedance.com>,
        Michal Hocko <mhocko@suse.com>,
        Muchun Song <muchun.song@linux.dev>,
        Linux-MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 2/7] mm: shrinker: Add a .to_text() method for shrinkers
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On Wed, Dec 06, 2023 at 07:16:04PM +1100, Dave Chinner wrote:
> On Fri, Dec 01, 2023 at 12:01:33PM -0800, Roman Gushchin wrote:
> > What would be the proper solution to this problem from your point of view?
> > What functionality/API mm can provide to make the life of fs developers
> > better here?
> 
> What can we do better?
> 
> The first thing we can do better that comes to mind is to merge
> Kent's patches that allow the shrinker owner to output debug
> information when requested by the infrastructure.
> 
> Then we - the shrinker implementers - have some control of our own
> destiny.  We can add whatever we need to solve shrinker and OOM
> problems realted to our shrinkers not doing the right thing.
> 
> But without that callout from the infrastructure and the
> infrastructure to drive it at appropriate times, we will make zero
> progress improving the situation. 
> 
> Yes, the code may not be perfect and, yes, it may not be useful to
> mm developers, but for the people who have to debug shrinker related
> problems in production systems we need all the help we can get. We
> certainly don't care if it isn't perfect, just having something we
> can partially tailor to our iindividual needs is far, far better
> than the current situation of nothing at all...

Of course if mm people don't want it I've got better things to do than
fight uphill battles just to get some reviewed-by tags. Real high
quality review feedback in this thread.