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Date: Mon, 21 Oct 2013 08:44:00 +0800
From: Julian Elischer <julian@freebsd.org>
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To: Colin Percival <cperciva@freebsd.org>, freebsd-net@freebsd.org
Subject: Re: LRO causing stretch ACK violations interacts badly with delayed
 ACKing
References: <52605EC9.6090406@freebsd.org>
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On 10/18/13 6:03 AM, Colin Percival wrote:
> Hi all,
>
> I know {TSO, LRO, ACKing policy} has been discussed here recently, and I don't
> want to rehash everything, but I'm seeing some very bad misbehaviour with LRO
> and delayed ACKing turned on.
>
> Running 'fetch -o /dev/null https://www.amazon.com/' on an EC2 instance running
[...]
is this just for -current?
> Out of 142 ms that this TCP connection is alive, 100 ms was wasted.  This seems
> like something which ought to be fixed...
>