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Message-ID: <5283655b-b8c6-43da-939e-5a0d088caad6@bytedance.com>
Date:   Thu, 19 Oct 2023 19:21:48 +0800
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Subject: Re: Re: [PATCH net-next v2 3/3] sock: Fix improper heuristic on
 raising memory
To:     Shakeel Butt <shakeelb@google.com>
Cc:     "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20231016132812.63703-1-wuyun.abel@bytedance.com>
 <20231016132812.63703-3-wuyun.abel@bytedance.com>
 <CALvZod6FRH2cp2D2uECeAesGY575+mE_iyFwaXVJMbfk1jvcgQ@mail.gmail.com>
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From:   Abel Wu <wuyun.abel@bytedance.com>
In-Reply-To: <CALvZod6FRH2cp2D2uECeAesGY575+mE_iyFwaXVJMbfk1jvcgQ@mail.gmail.com>
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On 10/16/23 11:52 PM, Shakeel Butt Wrote:
> On Mon, Oct 16, 2023 at 6:28 AM Abel Wu <wuyun.abel@bytedance.com> wrote:
>>
>> Before sockets became aware of net-memcg's memory pressure since
>> commit e1aab161e013 ("socket: initial cgroup code."), the memory
>> usage would be granted to raise if below average even when under
>> protocol's pressure. This provides fairness among the sockets of
>> same protocol.
>>
>> That commit changes this because the heuristic will also be
>> effective when only memcg is under pressure which makes no sense.
>> Fix this by reverting to the behavior before that commit.
>>
>> After this fix, __sk_mem_raise_allocated() no longer considers
>> memcg's pressure. As memcgs are isolated from each other w.r.t.
>> memory accounting, consuming one's budget won't affect others.
>> So except the places where buffer sizes are needed to be tuned,
>> allow workloads to use the memory they are provisioned.
>>
>> Fixes: e1aab161e013 ("socket: initial cgroup code.")
>> Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
> 
> Acked-by: Shakeel Butt <shakeelb@google.com>

Thanks!