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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: 4966E2000398DA5B X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi David, I'm somewhat against adding more metrics which try to approximate availability of memory when we already know it not to generally manifest very well in practice, especially since this *is* calculable by userspace (albeit with some knowledge of mm internals). Users and applications often vastly overestimate the reliability of these metrics, especially since they heavily depend on transient page states and whatever reclaim efficacy happens to be achieved at the time there is demand. What do you intend to do with these metrics and how do you envisage other users should use them? Is it not possible to rework the strategy to use pressure information and/or workingset pressurisation instead? Thanks, Chris