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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) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: x3rs9dz6qinye8my3okaxae39jm8bo9s X-Rspamd-Queue-Id: ACA6CC0004 X-Rspamd-Server: rspam06 X-HE-Tag: 1782461800-781343 X-HE-Meta: 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 gV+r58KN NcFzwYvnMfWCTb3s3J6ur4cqIFKBRqTlFEbvNQD4eW7LtscqeltcICcK4Du3/55qw9bDFoL2F03/2+B2Xi3HDDOL7KiLQSt10HMdnzNlDTcRO8VRmY2sTIxqpbOeXF5WqJNMVK3oT52Y3Ti3EKQnb31GecimwKA7eDv2c1pc5qqgMf/X7XRocmfwkWBspRvnz3eYtF3aezpTeD5dbJyLTSMYOeZiViAGXFHw3yGc8ZYJPunrWHGzYEDxb23KnXizmHsepVdhL7r/DuM7ZV6EtT3XyEry9lewUQnL+D/EhFy6eNK/+LRW3mQg73M2J/cT9pO0syWvlQk6lnQF2+QSBcFXPySXonsrHKT340/jrRSyweO04Mpr/aawKFoy2x+T5dfMdix/74/y30Fb11hjsic7dG/D2etC/AJphMeA0lJHAN0lJj/P3JrXm4t/sMbTl1SQwyofR1ChGI0QkyHlXyUJ56uWURK72/6qQjrgrYFaqszI= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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