Subject: Re: multiple Tx queues
To: Jason Thorpe <thorpej@wasabisystems.com>
From: Sean Doran <smd@ab.use.net>
List: tech-net
Date: 01/10/2004 04:44:15
On 8 Jan, 2004, at 01:09, Jason Thorpe wrote:
> But we're not talking about N paths, here. We're talking about one
> path that can queue the packet multiple ways.
These are idempotent.
What you are suggesting is that aggregation will always hide the
various queueing behaviours behind a single abstraction boundary you
call "one path". Although the past is not always a good predictor of
the future, the past suggests strongly that this is wildly optimistic;
moreover the present has ugly examples of deaggregation at L2 (discrete
MPLS LSPs for specific DSCPs).
I would not be willing to take an apocalypse-started-by-this-approach
bet, however I also would not be willing to bet that the abstraction
boundary will remain forever contained within the radius of a single
hop, or within a single network.
If you really want your mind bent, take a look at the multimetic
routing literature, such as it is. Nobody's got a good handle on it.
(Of course, I want to deploy it operationally a year from now...)
Sean.
PS - diffserv has become sexy and popular in many enterprise settings;
for that reason in particular, it probably makes sense to follow Erik's
suggestion and "upgrade" from TOS-think to diffserv-think in netbsd.