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[109.81.83.7]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47fb6b18a9fsm5229420f8f.32.2026.07.29.01.02.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Jul 2026 01:02:23 -0700 (PDT) Date: Wed, 29 Jul 2026 10:02:22 +0200 From: Michal Hocko To: Guopeng Zhang Cc: Johannes Weiner , Roman Gushchin , Shakeel Butt , Andrew Morton , Muchun Song , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Guopeng Zhang Subject: Re: [PATCH] mm: memcg: stop reclaim when a limit update is superseded Message-ID: References: <20260724021805.1234583-1-guopeng.zhang@linux.dev> <615d091c-bd3b-4686-817e-5b29756542ff@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed 29-07-26 14:15:25, Guopeng Zhang wrote: > > > 在 2026/7/27 21:58, Michal Hocko 写道: > > On Mon 27-07-26 20:59:23, Guopeng Zhang wrote: > >> > >> > >> 在 2026/7/27 16:16, Michal Hocko 写道: > >>> On Fri 24-07-26 10:18:05, Guopeng Zhang wrote: [...] > > Is this trying to replicate any real workload? One would expect that > > writers to limit do some sort of coordination otherwise the exact > > behavior is not really well defined. > > > > No, this was not motivated by a reported production workload. We found > it through automated randomized testing for our cgroup observability > work and reduced it to the reproducer above. This is an important detail to be mentioned in the changelog. Describing motivation for a change is really important, especially if it has direct impact in user interface behavior. -- Michal Hocko SUSE Labs