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Howlett" , Suren Baghdasaryan , Christoph Lameter , "Paul E. McKenney" , Tejun Heo , Johannes Weiner , Davidlohr Bueso , Namhyung Kim , linux-mm@kvack.org Subject: Re: MM global locks as core counts quadruple Message-ID: References: <07e7d078-0c9d-6a1f-1ab5-295f86974b72@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <07e7d078-0c9d-6a1f-1ab5-295f86974b72@google.com> X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 4DB1C140012 X-Stat-Signature: nd6ujsrfok1sc1514qjtiq5b94ah17xs X-HE-Tag: 1718935310-920551 X-HE-Meta: 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 nxzc0A0C 9o8fCx0m6MVDL0pmsq/6NNEL0sYiMWIiiA9yT1s+IzVQWM4IiU8EI+1da+jAd9ia1zfNe7hdpJ6LmBU+9/GZofo2huRKibC+SfoAuWxoUaZrLuepqMX2hf4r/Def2P42DVVSBJjox56qkbiP6jAS8Jayfjk5w4GsgZW9Fc2/ZHtG8I31BahrpgarG5f9GqBF1ElyVkT3AIBu3qwA= 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 Thu, Jun 20, 2024 at 05:35:45PM -0700, David Rientjes wrote: > - slab_mutex This is weird. You must have very strange workloads running ;-) It protects the list of slabs. So it's taken for - Slab creation / destruction - CPU online/offline - Memory hotplug - Reading /proc/slabinfo All of these should be rare events, but don't seem to be for you?