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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> Precedence: bulk X-Mailing-List: linux-trace-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: <162c241c-8dd9-4700-a538-0a308de2de8d@efficios.com> 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