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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 947AD16002C X-Stat-Signature: pdyezfur9nzk4h66sqe6g87ksqisaiw1 X-Rspam-User: X-HE-Tag: 1701279267-509376 X-HE-Meta: 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 NsaqMl7x GVihGqI839jrDyXKXyeOeHYvhl9naGeLFhFb44wN7I0+gbMj4wI+AUvgKuJbU6gyHCThSMrGdeIskQSdfEG0LkhApLpgbRGk7pXZTdRpECQ1mHFJTo0oW+4ULmkupZjRnLqhh5huVylK5ixbMsy8T1nOXTd2X3h9pz8hcuQiLNkO8/MEaKRSdtpaqI60/xEjeLsVZSEV9ehU0n9eyOo0HzGNslpOQs5N/U6hGvq2IqwCYmKsi3+Ym4wfhplHeSRs4IM/5fZ3aO2P7SeW9yD2BqEgBvnwj7ZWQ0LiEOFWwDzzwih/YgnPVGQNWh/Rsv3xUa8zH3lOmLVohrh/oOH1nZLKh2wAZMMho+Wf7 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 Wed, 29 Nov 2023 18:10:33 +0100 Michal Hocko wrote: > > > How? You are only reporting the number of reclaimed pages and no > > > reclaimed pages could be not just because of low/min limits but > > > generally because of other reasons. You would need to report also the > > > number of scanned/isolated pages. > > > > > > > From my perspective, if memory control group (memcg) protection > > restrictions occur, we can identify them by the absence of the end() > > pair of begin(). Other reasons will have both tracepoints raised. > > That is not really great way to detect that TBH. Trace events could be > lost and then you simply do not know what has happened. Note, you can detect dropped events. If there's a dropped event, you can ignore the "missing end" from a beginning. You could also make synthetic events that pair an end event with a beginning event (which uses the last begin event found). Synthetic event creation is not affected by dropped events. There's a lot you can to get information with the prospect of dropped events. I would not use that as rationale for not using events. -- Steve