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AFAICS we have > > > mm_vmscan_lru_isolate > > > mm_vmscan_lru_shrink_active > > > mm_vmscan_lru_shrink_inactive > > > > > > which are in the vry core of the memory reclaim. Sure post processing > > > those is some work. > > > > Sure, you are absolutely right. In the usual scenario, the memcg > > shrinker utilizes two sub-shrinkers: slab and LRU. We can enable the > > tracepoints you mentioned and analyze them. However, there is one > > potential issue. Enabling these tracepoints will trigger the reclaim > > events show for all pages. Although we can filter them per pid, we > > cannot filter them per cgroup. Nevertheless, there are times when it > > would be extremely beneficial to comprehend the effectiveness of the > > reclaim process within the relevant cgroup. For this reason, I am adding > > the cgroup name to the memcg tracepoints and implementing a cumulative > > tracepoint for memcg shrink (LRU + slab)." > > I can see how printing memcg in mm_vmscan_memcg_reclaim_begin makes it > easier to postprocess per memcg reclaim. But you could do that just by > adding that to mm_vmscan_memcg_reclaim_{begin, end}, no? Why exactly > does this matter for kswapd and other global reclaim contexts? >From my point of view, kswapd and other non-direct reclaim paths are important for memcg analysis because they also influence the memcg reclaim statistics. The tracepoint mm_vmscan_memcg_reclaim_{begin, end} is called from the direct memcg reclaim flow, such as: - a direct write to the 'reclaim' node - changing 'max' and 'high' thresholds - raising the 'force_empty' mechanism - the charge path - etc. However, it doesn't cover global reclaim contexts, so it doesn't provide us with the full memcg reclaim statistics. -- Thank you, Dmitry