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Subject: Re: [PATCH net-next] tcp: replace LINUX_MIB_TCPOFODROP with
 LINUX_MIB_TCPRMEMFULLDROP for drops due to receive buffer full
To:     Yafang Shao <laoar.shao@gmail.com>, edumazet@google.com,
        davem@davemloft.net
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1530100216-13070-1-git-send-email-laoar.shao@gmail.com>
From:   Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <c89b70f9-e70d-35a5-b9a7-7e3ed7d34edf@gmail.com>
Date:   Wed, 27 Jun 2018 07:48:54 -0700
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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.

Thanks.