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This traversal scales >> with the number of memcgs, even when LRU_GEN is runtime-disabled. > > Can you please look into removing the memcg LRU instead? > > Use mem_cgroup_iter() with a reclaim cookie in shrink_many(), like we > do in shrink_node_memcgs(). > > The memcg LRU is complicated, and it only works for global reclaim; if > you have a subtree with a memory.max at the top, it'll go through > shrink_node_memcgs() already anyway. Hi, all, I previously attempted to remove the memcg LRU [1], but this change introduced a regression that increased kswapd overhead significantly. Now circling back to this issue: does anyone have suggestions on how to address this problem effectively? [1] https://lore.kernel.org/cgroups/0b8ea26f-71f7-4f6d-b0d6-7d42e087a7ed@huaweicloud.com/T/#t -- Best regards, Ridong