tcp_xmit_timer()

[Christian Vogt]

Yes, and this (from sys/netinet/tcp_var.h):

    #define TCP_RTTVAR_SCALE   16   /* multiplier for rttvar; 2 bits */
    #define TCP_RTTVAR_SHIFT   4    /* shift for rttvar; 2 bits */

...should say "...for rttvar; 4 bits frac." in both places.

- Christian

-- 
Christian Vogt, Institute of Telematics, University of Karlsruhe
www.tm.uka.de/~chvogt/pubkey/



John-Mark Gurney wrote:
> 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...
>