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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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: scrcdymfqchgmu9g717pfjgbedbokway X-Rspamd-Queue-Id: 18906160006 X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1774538647-818715 X-HE-Meta: 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 PpK/P62X A3isFPhm9pG6fW6nBhnjDPpmoDwrJqymh+U3cDkAJnb8MYRHNuVFjEd9j1sl7AcQqtMeH4Cp6vEhSl4OI8F2rSCBw6+3JauG/xx2aSTECwjMVAGA0NEjWLWzdpuNpdbvo0me1Snge6fbrDnonMjnIBUf4qLm08rBvgdF73sNP+EWadydXMWA/7Nrg71ESEr74WvTnXiuSTvHDFgVpPXDB6h7Hcdw41LCoARw+yxboTJZJu/KAUmr4GEe28r6PRm/7FceMXuYsXBSsU7b0MWCr3jJctGdd9VQOltr8iLyNgw8o+0ywdH7Gn3hynU7YsukYUPeOLllwbxjpiX07+bY5WY2masc0z0YVxS7eMXsXRem01jdtr6k2zXJlIxYoTmp7CjEi90YezOBV3HKnEiuzh6WyRw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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