On Thu, 7 May 2020 18:59:46 -0300 "Guilherme G. Piccoli" <gpiccoli@xxxxxxxxxxxxx> wrote: > Currently we have no way to determine if compaction was triggered > by sysctl write, but this is an interesting information to have, > specially in systems with high uptime that presents lots of > fragmented memory. There's no statistic indicating if compaction > was triggered manually or ran by Linux itself, the vmstat numbers > cannot tell the user this information. Could add it to vmstat? > This patch adds a very simple message to kernel log when compaction > is requested through a write to sysctl file, and also it accumulates > the number of previously manual compaction executions. It follows > the approach used by drop_caches. Userspace could write to /dev/kmsg when it decides to trigger compaction? Although using the kernel log seems a fairly lame way for userspace to record its own actions...
