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Date:   Thu, 30 Nov 2023 19:00:20 -0500
From:   Kent Overstreet <kent.overstreet@linux.dev>
To:     Roman Gushchin <roman.gushchin@linux.dev>
Cc:     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>,
        Dave Chinner <david@fromorbit.com>
Subject: Re: [PATCH 2/7] mm: shrinker: Add a .to_text() method for shrinkers
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On Thu, Nov 30, 2023 at 11:01:23AM -0800, Roman Gushchin wrote:
> Ok, a simple question then:
> why can't you dump /proc/slabinfo after the OOM?
> 
> Unlike anon memory, slab memory (fs caches in particular) should not be heavily
> affected by killing some userspace task.

Well, currently the show_mem report dumps slab info if unreclaimable
slab usage is over some threshold (50%?). So it already does what you
describe - sometimes.

One of the patches in this series trims that down to make it more
useful; reporting on only the top 10 slabs, by mmeory usage, in sorted
order and with human readable units.