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From:   Yafang Shao <laoar.shao@gmail.com>
Date:   Wed, 27 Jun 2018 23:14:30 +0800
Message-ID: <CALOAHbCdRjq2n37GpeBdorcbxXMDX2vNDLftypViJd5hRTA28A@mail.gmail.com>
Subject: Re: [PATCH net-next] tcp: replace LINUX_MIB_TCPOFODROP with
 LINUX_MIB_TCPRMEMFULLDROP for drops due to receive buffer full
To:     Eric Dumazet <eric.dumazet@gmail.com>
Cc:     Eric Dumazet <edumazet@google.com>,
        David Miller <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Wed, Jun 27, 2018 at 10:48 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
>
> On 06/27/2018 04:50 AM, Yafang Shao wrote:
>> When sk_rmem_alloc is larger than the receive buffer and we can't
>> schedule more memory for it, the skb will be dropped.
>>
>> In above situation, if this skb is put into the ofo queue,
>> LINUX_MIB_TCPOFODROP is incremented to track it,
>> while if this skb is put into the receive queue, there's no record.
>>
>> So LINUX_MIB_TCPOFODROP is replaced with LINUX_MIB_TCPRMEMFULLDROP to track
>> this behavior.
>
>
> Hi Yafang
>
> I do not want to remove TCPOFODrop and mix multiple causes in one single counter.
>
> Please take a look at commit a6df1ae9383697c to have the reasoning.
>

Got it!

What about introduce a new counter, i.e. TCPRcvQFullDrop ?

Thanks
Yafang