[1503] in linux-net channel archive
Re: double acks?
daemon@ATHENA.MIT.EDU (Alan Cox)
Fri Dec 8 08:04:41 1995
From: iialan@iifeak.swan.ac.uk (Alan Cox)
To: erb@inss1.etec.uni-karlsruhe.de
Date: Thu, 7 Dec 1995 15:57:07 +0000 (GMT)
Cc: linux-net@vger.rutgers.edu
In-Reply-To: <199512062132.WAA07062@insl2.etec.uni-karlsruhe.de> from "Olaf Erb" at Dec 6, 95 10:32:25 pm
> I'm wondering if anyone hasn't noticed that Linux always sends double
> acks on tcp sessions. Just a little example:
>
> 44.130.41.11.1186 > 44.130.29.32.79: P 1:3(2) ack 1 win 432
> Data (2): ^M^J (DF)
> 44.130.29.32.79 > 44.130.41.11.1186: . ack 3 win 1024
> 44.130.29.32.79 > 44.130.41.11.1186: . ack 3 win 1024
>
> This is on a very slow radio link. The same happens on slip, and
> on other slow links (100ms rtt is enough to get 2 acks).
> (tested on 1.2.13, 1.3.45).
It needs someone to implement delayed ack support. Most of the bits for it
are present.
Alan
