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Tue, 27 Feb 2024 13:17:40 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id YL61IPTg3WWDLAAAD6G6ig (envelope-from ); Tue, 27 Feb 2024 13:17:40 +0000 Date: Tue, 27 Feb 2024 14:17:40 +0100 From: Michal Hocko To: Yafang Shao Cc: Yosry Ahmed , akpm@linux-foundation.org, hannes@cmpxchg.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, linux-mm@kvack.org Subject: Re: [RFC PATCH] mm: Add reclaim type to memory.reclaim Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Spamd-Bar: / X-Rspamd-Queue-Id: C824D180002 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 3ni7c9j6sikenz517rim3owxsjimgmdx X-HE-Tag: 1709039863-652953 X-HE-Meta: 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 Zog== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000184, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue 27-02-24 20:12:27, Yafang Shao wrote: > On Tue, Feb 27, 2024 at 8:09 PM Yafang Shao wrote: [...] > > > If that's the case, why was slabs info initially exposed through > > > /proc/slabinfo? because that helps to better understand the memory consumption by slab consumers. > > > Isn't that level of detail considered a kernel > > > implementation detail? Currently, users can identify which slab is > > > consuming the most memory but lack the ability to take action based on > > > that information. This suggests a flaw in the kernel implementation. I disgree! > > BTW, we even expose more detailed kernel implementation details > > through /sys/kernel/slab. > > That is really confusing... > > There is even a /sys/kernel/slab/dentry/shrink .... > oh please... We also have /proc/sys/vm/drop_caches and we have learned those are really terrible interfaces and we have good reasons to not replicate those into memcg interfaces. Using bad interfaces as an example is not the way argue for new ones. -- Michal Hocko SUSE Labs