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Date: Mon, 4 Jul 2005 12:14:28 -0700
From: John-Mark Gurney <gurney_j@resnet.uoregon.edu>
To: Christian Vogt <chvogt@tm.uka.de>
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Cc: freebsd-net@freebsd.org, TM-RO2 <tm-ro2@tm.uka.de>
Subject: Re: tcp_xmit_timer()
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Christian Vogt wrote this message on Mon, Jul 04, 2005 at 20:58 +0200:
> Hi everybody,
> 
> just a nit in sys/netinet/tcp_input.c:tcp_xmit_timer().  A comment says:
> 
>    /*
>     * srtt is stored as fixed point with 5 bits after the
>     * binary point (i.e., scaled by 8).  The following magic
>     * is equivalent to the smoothing algorithm in rfc793 with
>     * an alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed
>     * point).  Adjust rtt to origin 0.
>     */
> 
> But it should say "...(i.e., scaled by 32)".
> 
> Hope this wasn't mentioned before on this list.

This isn't the only mismatch:
#define     TCP_RTT_SHIFT           5       /* shift for srtt; 3 bits frac. */

Maybe wollman can shed light on this?  It looks like he just didn't
update the comments in both places...

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."