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charset=us-ascii Content-Disposition: inline In-Reply-To: <1585221127-11458-1-git-send-email-laoar.shao@gmail.com> 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: On Thu, Mar 26, 2020 at 07:12:05AM -0400, Yafang Shao wrote: > PSI gives us a powerful way to anaylze memory pressure issue, but we can > make it more powerful with the help of tracepoint, kprobe, ebpf and etc. > Especially with ebpf we can flexiblely get more details of the memory > pressure. > > In orderc to achieve this goal, a new parameter is added into > psi_memstall_{enter, leave}, which indicates the specific type of a > memstall. There're totally ten memstalls by now, > MEMSTALL_KSWAPD > MEMSTALL_RECLAIM_DIRECT > MEMSTALL_RECLAIM_MEMCG > MEMSTALL_RECLAIM_HIGH > MEMSTALL_KCOMPACTD > MEMSTALL_COMPACT > MEMSTALL_WORKINGSET_REFAULT > MEMSTALL_WORKINGSET_THRASHING > MEMSTALL_MEMDELAY > MEMSTALL_SWAPIO What does this provide over the events tracked in /proc/vmstats? Can you elaborate a bit how you are using this information? It's not quite clear to me from the example in patch #2.