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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49268fef710sm106993125e9.7.2026.06.26.01.16.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Jun 2026 01:16:38 -0700 (PDT) Date: Fri, 26 Jun 2026 09:16:37 +0100 From: David Laight To: "Zach O'Keefe" Cc: Dave Hansen , "H. Peter Anvin" , David Stevens , Pasha Tatashin , Linus Walleij , Will Deacon , Quentin Perret , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Andy Lutomirski , Xin Li , Peter Zijlstra , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Uladzislau Rezki , Kees Cook , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2 00/13] Dynamic Kernel Stacks Message-ID: <20260626091637.484ee07d@pumpkin> In-Reply-To: References: <20260424191456.2679717-1-stevensd@google.com> <6369e5ce-74e3-4c68-8053-d7d7d21b6955@zytor.com> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) 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-Transfer-Encoding: 7bit On Thu, 18 Jun 2026 07:50:26 -0700 "Zach O'Keefe" wrote: ... > Dave, > > Necroing this thread, as the potential aggregate savings continue to > stand out for us on the datacenter side (whereas David is motivated > separately, from the consumer device side). What are the other kernel memory costs associated with each thread? While thinks like ps used to assume it was just 4k, it won't be any more. Even for user threads many things that used to be per-process aren't any more either. But just the task structure and FP save area are non-trivial. David L