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Date:   Fri, 18 Feb 2022 10:56:44 -0800 (PST)
From:   David Rientjes <rientjes@google.com>
To:     Yu Zhao <yuzhao@google.com>, Johannes Weiner <hannes@cmpxchg.org>,
        Shakeel Butt <shakeelb@google.com>
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        Shuang Zhai <szhai2@cs.rochester.edu>,
        Sofia Trinh <sofia.trinh@edi.works>
Subject: Re: [page-reclaim] [PATCH v7 11/12] mm: multigenerational LRU:
 debugfs interface
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On Tue, 8 Feb 2022, Yu Zhao wrote:

> Add /sys/kernel/debug/lru_gen for working set estimation and proactive
> reclaim. These features are required to optimize job scheduling (bin
> packing) in data centers [1][2].
> 

Johannes, do you believe this interface is sufficient to induce memcg 
based reclaim or do you have plans to propose a memory.reclaim extension 
to memcg?

I assume that lru_gen could be used even if memcg is disabled whereas 
memory.reclaim would only be available on systems where the controller is 
mounted through cgroups.

Yet a question would probably arise about the stability of this interface 
since it lives in debugfs: can we plan on /sys/kernel/debug/lru_gen being 
long-term supported?