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charset="UTF-8" X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: A5CB31C0030 X-Stat-Signature: w13ymzaoqmeutdepsaiwfxirwdqi8acz X-Rspam-User: X-HE-Tag: 1673456693-685323 X-HE-Meta: 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 +94mz1sE cLYP6RsCc/LCeJ/f+r+b/MbJY/vz8GSgv0sqnPAehToofOuUhRZ0FWm4I/VgoFg0svVoHiFaknnqiXmrtu76bZgtK6PPb0HAphzWQ 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: On Wed, Jan 11, 2023 at 8:44 AM Michal Hocko wrote: > > On Wed 11-01-23 08:28:49, Suren Baghdasaryan wrote: > [...] > > Anyhow. Sounds like the overhead of the current design is small enough > > to remove CONFIG_PER_VMA_LOCK and let it depend only on architecture > > support? > > Yes. Further optimizations can be done on top. Let's not over optimize > at this stage. Sure, I won't optimize any further. Just to expand on your question. Original design would be problematic for embedded systems like Android. It notoriously has a high number of VMAs due to anonymous VMAs being named, which prevents them from merging. 2M per process increase would raise questions, therefore I felt the need for optimizing the memory overhead which is done in the last patch. Thanks for the feedback! > -- > Michal Hocko > SUSE Labs