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From:   Yafang Shao <laoar.shao@gmail.com>
Date:   Mon, 24 Sep 2018 20:39:08 +0800
Message-ID: <CALOAHbD00L_dNTp=ETh26Wi+Mw-dKt3_PYq2Pc2oS0GiGxkOXA@mail.gmail.com>
Subject: Re: [PATCH net-next] tcp: expose sk_state in tcp_retransmit_skb tracepoint
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 Mon, Sep 24, 2018 at 5:42 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
>
> On 09/23/2018 12:49 PM, Yafang Shao wrote:
>> With sk_state, we can know whether this connection is in SYN_SENT state
>> or ESTBLISHED state.
>> The reason to distinguish between these two scenario is that the
>> retransmission in ESTABLISHED state always mean network congestion while
>> in SYN_SENT state it always mean server issue, i.e. the syn packet is
>> dropped due to syn backlog queue full.
>
> You mean, a packet drop on the remote peer ?
>

Yes, I mean drop on the remote peer.

> It could also be a packet drop in the network.
>

Yes of course.

> Your patch is good, but changelog is quite misleading.

Will modify the changelog.


Thanks
Yafang