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[109.81.31.149]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43b919cf2d3sm8479963f8f.19.2026.03.26.08.24.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Mar 2026 08:24:05 -0700 (PDT) Date: Thu, 26 Mar 2026 16:24:04 +0100 From: Michal Hocko To: Shakeel Butt Cc: lsf-pc@lists.linux-foundation.org, Andrew Morton , Johannes Weiner , David Hildenbrand , Qi Zheng , Lorenzo Stoakes , Chen Ridong , Emil Tsalapatis , Alexei Starovoitov , Axel Rasmussen , Yuanchu Xie , Wei Xu , Kairui Song , Matthew Wilcox , Nhat Pham , Gregory Price , Barry Song <21cnbao@gmail.com>, David Stevens , Vernon Yang , David Rientjes , Kalesh Singh , wangzicheng , "T . J . Mercier" , Baolin Wang , Suren Baghdasaryan , Meta kernel team , bpf@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [LSF/MM/BPF TOPIC] Towards Unified and Extensible Memory Reclaim (reclaim_ext) Message-ID: References: <20260325210637.3704220-1-shakeel.butt@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=us-ascii Content-Disposition: inline In-Reply-To: On Thu 26-03-26 06:44:07, Shakeel Butt wrote: > On Thu, Mar 26, 2026 at 08:12:10AM +0100, Michal Hocko wrote: > > On Wed 25-03-26 14:06:37, Shakeel Butt wrote: [...] > > I think we should focus to make a single canonical reclaim > > implementation work well. I.e. we deal with most (or ideally all) known > > regressions of MGLRU. > > Here we disagree on the approach or steps to reach the single canonical reclaim > implementation. MGLRU is a plethora of different mechanisms and policies and it > never went through rigorous evaluation for each of those mechanisms and > policies individually. To me that needs to be done to have one solution. If my recollection is correct from the LSFMM (2022) there was a promise that MGLRU architecture should allow to add extension and eventually supersede traditional LRU. If we do not see that happening then we should re-evaluate current MGRLU approach. I do not think we want to build reclaim_ext architecture on top of the current code. Or are you suggesting to achieve MGLRU through reclaim_ext? -- Michal Hocko SUSE Labs