Re: [PATCH net-next] tcp: expose sk_state in tcp_retransmit_skb tracepoint
From: Yafang Shao
Date: Mon Sep 24 2018 - 08:39:52 EST
On Mon, Sep 24, 2018 at 5:42 AM, Eric Dumazet <eric.dumazet@xxxxxxxxx> 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