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Tue, 24 Nov 2020 05:47:18 -0800 (PST) MIME-Version: 1.0 References: <20201124105836.713371-1-atomlin@redhat.com> <20201124112612.GV27488@dhcp22.suse.cz> <20201124133644.GA31550@dhcp22.suse.cz> In-Reply-To: <20201124133644.GA31550@dhcp22.suse.cz> From: Aaron Tomlin Date: Tue, 24 Nov 2020 13:47:07 +0000 Message-ID: Subject: Re: [PATCH] memcg: add support to generate the total count of children from root To: Michal Hocko Cc: linux-kernel , hannes@cmpxchg.org, vdavydov.dev@gmail.com, Andrew Morton , cgroups@vger.kernel.org, linux-mm Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=atomlin@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 24 Nov 2020 at 13:36, Michal Hocko wrote: Michal, > This like any other user visible interface would be a much easier sell > if there was a clear usecase to justify it. I do not see anything > controversial about exporting such a value but my general take is that > we are only adding new interface when existing ones are insufficient. A > performance might be a very good reason but that would really require to > come with some real life numbers. Fair enough and understood. At this stage, I unfortunately do not have such supporting data. This was only useful in an isolated situation. Having said this, I thought that the aforementioned interface would be helpful to others, in particular, given the known limitation. Kind regards, -- Aaron Tomlin