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[109.81.86.79]) by smtp.gmail.com with UTF8SMTPSA id ffacd0b85a97d-3b79c4a2f03sm14103393f8f.72.2025.08.03.22.52.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 03 Aug 2025 22:52:12 -0700 (PDT) Date: Mon, 4 Aug 2025 07:52:10 +0200 From: Michal Hocko To: zhongjinji@honor.com Cc: linux-mm@kvack.org, akpm@linux-foundation.org, rientjes@google.com, shakeel.butt@linux.dev, npache@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, peterz@infradead.org, dvhart@infradead.org, dave@stgolabs.net, andrealmeid@igalia.com, liulu.liu@honor.com, feng.han@honor.com Subject: Re: [[PATCH v2] 2/2] futex: Only delay OOM reaper for processes using robust futex Message-ID: References: <20250801153649.23244-1-zhongjinji@honor.com> <20250801153649.23244-2-zhongjinji@honor.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20250801153649.23244-2-zhongjinji@honor.com> On Fri 01-08-25 23:36:49, zhongjinji@honor.com wrote: > From: zhongjinji > > After merging the patch > https://lore.kernel.org/all/20220414144042.677008-1-npache@redhat.com/T/#u, > the OOM reaper runs less frequently because many processes exit within 2 seconds. > > However, when a process is killed, timely handling by the OOM reaper allows > its memory to be freed faster. > > Since relatively few processes use robust futex, delaying the OOM reaper for > all processes is undesirable, as many killed processes cannot release memory > more quickly. Could you elaborate more about why this is really needed? OOM should be a very slow path. Why do you care about this potential improvement in that situation? In other words what is the usecase? -- Michal Hocko SUSE Labs