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[109.81.19.111]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-432bd0dacc5sm48487321f8f.5.2026.01.14.00.18.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Jan 2026 00:18:31 -0800 (PST) Date: Wed, 14 Jan 2026 09:18:29 +0100 From: Michal Hocko To: Mathieu Desnoyers Cc: Andrew Morton , linux-kernel@vger.kernel.org, "Paul E. McKenney" , Steven Rostedt , Masami Hiramatsu , Dennis Zhou , Tejun Heo , Christoph Lameter , Martin Liu , David Rientjes , christian.koenig@amd.com, Shakeel Butt , SeongJae Park , Johannes Weiner , Sweet Tea Dorminy , Lorenzo Stoakes , "Liam R . Howlett" , Mike Rapoport , Suren Baghdasaryan , Vlastimil Babka , Christian Brauner , Wei Yang , David Hildenbrand , Miaohe Lin , Al Viro , linux-mm@kvack.org, stable@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Yu Zhao , Roman Gushchin , Mateusz Guzik , Matthew Wilcox , Baolin Wang , Aboorva Devarajan Subject: Re: [PATCH v1 1/1] mm: Fix OOM killer and proc stats inaccuracy on large many-core systems Message-ID: References: <20260113194734.28983-1-mathieu.desnoyers@efficios.com> <20260113194734.28983-2-mathieu.desnoyers@efficios.com> <20260113134644.9030ba1504b8ea41ec91a3be@linux-foundation.org> <20260113155541.1da4b93e2acbb2b4f2cda758@linux-foundation.org> <162c241c-8dd9-4700-a538-0a308de2de8d@efficios.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <162c241c-8dd9-4700-a538-0a308de2de8d@efficios.com> X-Rspam-User: X-Stat-Signature: dqs3qjmf8xqb5pothw83xdq9bbgrc8gn X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 6FF1E1C0005 X-HE-Tag: 1768378713-207318 X-HE-Meta: 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 TNl9h+Cn KdSJRVx/N4edJGCPBGobV4oWrjdxuM3x3SYwgDEFHnaVNbo+UPvX3cGhRJvs2raRZwbTYaRdFk/ul6kHG6vvKvTt1+RzKY5wFZvA0pzxVhMhoqyxN7taGIS4PKpwf+OBWKoUBYirBaHChTZp613nmZ0xfVoJDO4piH01pXgFyi2Egi48bgwfqkkYLyPIdhlSKaB3ecZtH90qvNXjKPEquO4FYDdTJB4xIDJAnPEVOSDis1s0gszoB6abL2ntlb4f66wy+KgQoFb0zp4dU9HGQLEb9WB4HawoDwNbc8wzNhIff1T9S3OPKti9tbG/CykekfEtULg2St07cgJED6qa58//UyuJ5bHjoO2gVE7Cvf+nUHsbfy/Ztg0k3TsueDfhwDcgXPDto3+Qao3doNj7/dXD2zUBRyzSKaybE3Rv/nyK7O4r2zgGq8jV4amtvNN8WwX6pWT/CX3nbxDJEdT83COHEZLbOEK8FMgaK1oflpCM5QFY= 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: List-Subscribe: List-Unsubscribe: On Tue 13-01-26 20:22:16, Mathieu Desnoyers wrote: > On 2026-01-13 18:55, Andrew Morton wrote: > > On Tue, 13 Jan 2026 17:16:16 -0500 Mathieu Desnoyers wrote: > > > > > The hpcc series introduces an approximation which provides accuracy > > > limits on the approximation that make the result is still somewhat > > > meaninful on large many core systems. > > > > Can we leave the non-oom related parts of procfs as-is for now, then > > migrate them over to hpcc when that is available? Safer that way. > > Of course. > > So AFAIU the plan is: > > 1) update the oom accuracy fix to only use the precise sum for > the oom killer, no changes to procfs ABIs. This targets mm-new. > > 2) update the hpcc series to base them on top of the new fix from (1). > Update their commit messages to indicate that they bring accuracy > improvements to the procfs ABI on large many-core systems, as well as > latency improvements to the oom killer. This will target upstreaming > after the next merge window, but I will still post it soon to gather > feedback. > > Does that plan look OK ? I was about to propose the same. 1) is a regression fix and should be merged first and go to stable trees (it is a low priority fix but still worth having addressed). Also a minor nit. You do not have to send cover letter for a single patch series. Thanks for working on this Mathieu! -- Michal Hocko SUSE Labs