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charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.14.6 (2020-07-11) X-Rspamd-Queue-Id: 942BD180D0181 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: Shakeel Butt writes: >> Sometimes, memory reclaim may not be able to recover memory in a rate >> that can catch up to the physical memory allocation rate especially >> when rotating disks are used for swapping or writing dirty pages. In >> this case, the physical memory consumption will keep on increasing. > >Isn't this the real underlying issue? Why not make the guarantees of >memory.high more strict instead of adding more interfaces and >complexity? Oh, thanks Shakeel for bringing this up. I missed this in the original changelog and I'm surprised that it's mentioned, since we do have protections against that. Waiman, we already added artificial throttling if memory reclaim is not sufficiently achieved in 0e4b01df8659 ("mm, memcg: throttle allocators when failing reclaim over memory.high"), which has been present since v5.4. This should significantly inhibit physical memory consumption from increasing. What problems are you having with that? :-)