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charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20200908142456.89626-1-zangchunxin@bytedance.com> User-Agent: Mutt/1.14.6 (2020-07-11) X-Rspamd-Queue-Id: 0B11D1ACC35 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000701, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: drop_caches by its very nature can be extremely performance intensive -- if someone wants to abort after trying too long, they can just send a TASK_KILLABLE signal, no? If exiting the loop and returning to usermode doesn't reliably work when doing that, then _that's_ something to improve, but this looks premature to me until that's demonstrated not to work. zangchunxin@bytedance.com writes: >In one drop caches action, only traverse memcg once maybe is better. >If user need more memory, they can do drop caches again. Can you please provide some measurements of the difference in reclamation in practice?