Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 21 Jun 1998 22:28:38 -0700
From:      bmah@CA.Sandia.GOV (Bruce A. Mah)
To:        hackers@FreeBSD.ORG
Subject:   Re: TweakDUN 
Message-ID:  <199806220528.WAA14286@stennis.ca.sandia.gov>
In-Reply-To: Your message of "21 Jun 1998 15:21:54 EDT." <knzpf68srx.fsf@xena.mindspring.com> 

next in thread | previous in thread | raw e-mail | index | archive | help
--==_Exmh_-1673651679P
Content-Type: text/plain; charset=us-ascii

If memory serves me right, Robert Sanders wrote:
> bmah@CA.Sandia.GOV (Bruce A. Mah) writes:
> 
> > I don't use dialups very often nowadays, but I dimly remember trying to 
> > negotiate a *smaller* MTU on a downlink, in order to try to get better 
> > interactive performance (mumble mumble, use IP TOS bits and smarter queuein
> g, 
> Reordering packets doesn't help on a dialup link if you have a bulk
> transfer going with 1500 byte packets.  Even if you put "interactive"
> priority packets at the head of the queue, you may already have a 1500 
> byte packet in progress.

Yes to the second, no to the first.  If you have multiple, large packets 
queued at bottleneck link, the "interactive" packets don't wait for the 
remaining packets to get transmitted--they go first.  However, you're right 
that the serial link remains non-preemptive, so you do hurt from a long packet 
already in progress.

[snip]

> On
> the other hand, with my network architect's hat on I don't like the
> idea of tripling the rate of packets per sec through already busy
> major exchanges and core routers.

Good point, but I kinda wonder if the network architect working for 
whatever-ISP-it-was-that-started-this-discussion thought about this.  :-O

Cheers,

Bruce.



--==_Exmh_-1673651679P
Content-Type: application/pgp-signature

-----BEGIN PGP MESSAGE-----
Version: 2.6.2

iQCVAwUBNY3rhajOOi0j7CY9AQFQAAP9F4KQ90qbOrZdcrZUWyIFXd1qJjb1a1fQ
K3yqIg5igQ72Y7/0NIlkQQWa9DeLA2KoQjdfZUeR27HDDQ8Linc+8dVYTqWafKQ4
AW41uFyWTu5U5sk6v39LKa7LXuVKscUiSX9aT+8zSWmX9hqvf/+uSvwjLJwXfVLb
j57uaQguPR0=
=G74g
-----END PGP MESSAGE-----

--==_Exmh_-1673651679P--

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199806220528.WAA14286>