From mboxrd@z Thu Jan  1 00:00:00 1970
From: Neal Cardwell <ncardwell@google.com>
Subject: Re: [PATCH 2/4 net-next] tcp: prefer packet timing to TS-ECR for RTT
Date: Sun, 21 Jul 2013 23:17:44 -0400
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References: <1374385170-358-1-git-send-email-ycheng@google.com>
	<1374385170-358-2-git-send-email-ycheng@google.com>
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Cc: David Miller <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Nandita Dukkipati <nanditad@google.com>,
	Netdev <netdev@vger.kernel.org>
To: Yuchung Cheng <ycheng@google.com>
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On Sun, Jul 21, 2013 at 1:39 AM, Yuchung Cheng <ycheng@google.com> wrote:
> Prefer packet timings to TS-ecr for RTT measurements when both
> sources are available. That's because broken middle-boxes and remote
> peer can return packets with corrupted TS ECR fields. Similarly most
> congestion controls that require RTT signals favor timing-based
> sources as well. Also check for bad TS ECR values to avoid RTT
> blow-ups. It has happened on production Web servers.
>
> Signed-off-by: Yuchung Cheng <ycheng@google.com>

Acked-by: Neal Cardwell <ncardwell@google.com>