From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hagen Paul Pfeifer <hagen@jauu.net>
Subject: Re: [PATCH net-next] tcp: introduce TCPSpuriousRtxHostQueues SNMP
 counter
Date: Thu, 18 Apr 2013 20:19:50 +0200
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Cc: Stephen Hemminger <stephen@networkplumber.org>,
	David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Yuchung Cheng <ycheng@google.com>,
	Neal Cardwell <ncardwell@google.com>,
	Tom Herbert <therbert@google.com>,
	Willem de Bruijn <willemb@google.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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* Eric Dumazet | 2013-04-18 11:06:21 [-0700]:

>On Thu, 2013-04-18 at 10:45 -0700, Stephen Hemminger wrote:
>> On Thu, 18 Apr 2013 09:52:51 -0700
>> Eric Dumazet <eric.dumazet@gmail.com> wrote:
>> 
>> > From: Eric Dumazet <edumazet@google.com>
>> > 
>> > Host queues (Qdisc + NIC) can hold packets so long that TCP can
>> > eventually retransmit a packet before the first transmit even left
>> > the host.

Just out of curiosity: do you see effects of commit 9ad7c049 (initRTO from
3secs to 1sec) and a long standing queue? (with no path metric, rtt in
particular)

Hagen