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bh=mgQsT0odT754L8z+3U8Ly6+wQgAtpd/CnwwQT/eWbGI=; b=NNhnrtvLg8PfB8mUbc7N/HdOLXsPh/5OQiu6/44DHFXkC0f2rDOShtPI6i8AmkRnyQkfkf f/FD25+V3Qbkqh+Rngko70mZD/q5bcV7E8Z+PLl24rZAadbP5r4k3qo3OaXj7tnRDRRtQU OSy2FoNjadPlXc0Mxlo3tWXRjXaEQfg= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id A731313416; Tue, 14 Nov 2023 09:43:14 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id mqVVJzJBU2UgGAAAMHmgww (envelope-from ); Tue, 14 Nov 2023 09:43:14 +0000 Date: Tue, 14 Nov 2023 10:43:13 +0100 From: Michal Hocko To: Gregory Price Cc: "tj@kernel.org" , John Groves , Gregory Price , "linux-kernel@vger.kernel.org" , "linux-cxl@vger.kernel.org" , "linux-mm@kvack.org" , "cgroups@vger.kernel.org" , "linux-doc@vger.kernel.org" , "ying.huang@intel.com" , "akpm@linux-foundation.org" , "lizefan.x@bytedance.com" , "hannes@cmpxchg.org" , "corbet@lwn.net" , "roman.gushchin@linux.dev" , "shakeelb@google.com" , "muchun.song@linux.dev" , "jgroves@micron.com" Subject: Re: [RFC PATCH v4 0/3] memcg weighted interleave mempolicy control Message-ID: References: <20231109002517.106829-1-gregory.price@memverge.com> <0100018bb64636ef-9daaf0c0-813c-4209-94e4-96ba6854f554-000000@email.amazonses.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 34E934000A X-Stat-Signature: 3ew8yy9c7uj6mdurqdq8fyr3c66gmbkb X-HE-Tag: 1699954996-203706 X-HE-Meta: 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 T8lI5LgV 3c9e8H1LkUIZhqNwEqNmzmSM49Dvf9SIlpUA3RuiB4bUmriGVHxA+6Pm8MytIcQgY+z/KSBNfyG40khvaH0qmzZUkj/4c5dC5fKvjMu9wVmGqYFZAYJ6TWZ/FDljYGflIQAp0HX2QOarj7hKuLlc3DvE9WH01O667omTXdljaCOkN45SkVgdRCIToDZeEL1B6ot0W4rRV8330fizHNLnc7KyM+C8cjgnObGk/g9j04bWlluaGMqE6FU+FbFlbW0N667RdhUq1AGoydtsqbtYg/FTu81IeUaG/TLlhI+VRKfyhJA4= 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 Fri 10-11-23 22:42:39, Gregory Price wrote: [...] > If I can ask, do you think it would be out of line to propose a major > refactor to mempolicy to enable external task's the ability to change a > running task's mempolicy *as well as* a cgroup-wide mempolicy component? No, I actually think this is a reasonable idea. pidfd_setmempolicy is a generally useful extension. The mempolicy code is heavily current task based and there might be some challenges but I believe this will a) improve the code base and b) allow more usecases. That being said, I still believe that a cgroup based interface is a much better choice over a global one. Cpusets seem to be a good fit as the controller does control memory placement wrt NUMA interfaces. -- Michal Hocko SUSE Labs