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charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.14.7 (2020-08-29) 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: Chunxin Zang writes: >Please forgive me for not being able to understand why setting >memory.low for Type_A can solve the problem. >In my scene, Type_A is the most important, so I will set 100G to memory.low. >But 'memory.low' only takes effect passively when the kernel is >reclaiming memory. It means that reclaim Type_B's memory only when >Type_A in alloc memory slow path. This will affect Type_A's >performance. >We want to reclaim Type_B's memory in advance when A is expected to be busy. That's what kswapd reclaim is for, so this distinction is meaningless without measurements :-)