Re: TCP rto estimation patch

From: Horst von Brand
Date: Fri Apr 23 2004 - 12:38:00 EST

Wesley Eddy <weddy@xxxxxxxxxxxx> said:
> The TCP RTO estimation algorithm defined in RFC 2988 is followed properly
> in the kernel, however the constants alpha and beta in the specification
> are hardcoded as 3 and 2 everywhere they occur in the kernel. Since these
> constants crop up multiple times, this is poor programming practice. This
> patch binds the numeric values to symbols RTT_ALPHA and RTTVAR_BETA, and
> uses those symbolic values throughout the code. Since using 2 and 3 for
> these values is not mandatory, this makes tweaking them much easier.

Why RTT_ALPHA and RTTVAR_BETA, and not just RTT_BETA? Or even RTO_xxx?

Is there any reason to change them, ever? What happens if you change them?
Restrictions on values? All this should go with such a patch IMHO (at least
pointers to relevant discussion).

Must go over it with a fine comb to make sure no unrelated 2 or 3 got
replaced... out of my league, sorry.

Your patch is MIME-mangled, =3D, =20, =\n shows up all over the place here.
Dr. Horst H. von Brand User #22616
Departamento de Informatica Fono: +56 32 654431
Universidad Tecnica Federico Santa Maria +56 32 654239
Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513
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