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From:   Yu Zhao <yuzhao@google.com>
Date:   Wed, 18 Oct 2023 10:33:28 -0600
Message-ID: <CAOUHufaX35Y6MfwKj_XUWXJwdC=9M=g1gXpQpQghBZ2fXrkEAw@mail.gmail.com>
Subject: Re: [PATCH 0/3 RESEND] Per memcg lru_gen node stat
To:     Huan Yang <link@vivo.com>, "T.J. Mercier" <tjmercier@google.com>
Cc:     Jonathan Corbet <corbet@lwn.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Shakeel Butt <shakeelb@google.com>,
        Muchun Song <muchun.song@linux.dev>,
        Peter Xu <peterx@redhat.com>,
        David Hildenbrand <david@redhat.com>,
        "T.J. Alumbaugh" <talumbau@google.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Ryan Roberts <ryan.roberts@arm.com>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Suren Baghdasaryan <surenb@google.com>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>,
        "open list:MEMORY MANAGEMENT" <linux-mm@kvack.org>,
        "open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)" 
        <cgroups@vger.kernel.org>, opensource.kernel@vivo.com
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On Sun, Oct 8, 2023 at 8:57=E2=80=AFPM Huan Yang <link@vivo.com> wrote:
>
> On original global lru_gen node in debugfs, it can all show each memcg's
> lru gen info in "lru_gen" or "lru_gen_full", and can type cmd into lru_ge=
n.
> But which show info contains all memcg's info, and cmd need to
> know memcg's id.
>
> This patchset add lru_gen node in per memcg, with this node, we can
> get lru_gen info in each memcg.
> Also, we can type cmd to control each memcg's lru_gen seq, but, this node
> don't support multi cmd, single memcg just process one cmd once time.

Adding TJ from the Android team. (The other TJ you CC'ed is from the
ChromeOS team.)

This series introduced a new ABI, which has to be maintained forever.
How exactly would it be used in *production*?

Android doesn't officially support memcgs. So I want to understand the
real-world use cases first.