[3446] in linux-net channel archive
Re: shaper or whatever
daemon@ATHENA.MIT.EDU (Matthias Urlichs)
Mon Jun 24 07:09:45 1996
From: Matthias Urlichs <smurf@smurf.noris.de>
To: linux-net@vger.rutgers.edu
Date: Mon, 24 Jun 1996 12:51:50 +0100
In linux.dev.net, article <199606240811.JAA00553@snowcrash.cymru.net>,
Alan Cox <alan@cymru.net> writes:
>=20
> route add from cheap.customers default dev shaper0
>=20
Cool.
> I don't yet have routing by port.
>=20
I'd use the firewall code to select which routing entries to use, eithe=
r
with an additional interface to forward the traffic to, or with a minim=
um
metric the routes must have. (That would require NOT to toss high-metri=
c
routes whenever we add a low-metric route for the same destination/netm=
ask,
but IMHO that's a useless idea anyway.)
> may only move so far forward. When we add the frame we set its latenc=
y time
> to 0 and set the time it is clocked out of the shaper to be jiffies +
> times of packets ahead of us at that bit rate. Frames beyond us we mo=
ve
Why do you need to set the time when you add to the queue? It seems to =
me
that it'd be simpler to calculate that when sending, i.e. jiffies +
length-of-packet / bandwidth, with fixed-point arithmetic (or whatever)=
to
allow for rounding errors and small packets.
> this to its latency. Frames exceeding the latency boundary are droppe=
d. Its
I'd carry a counter for the bytes in the queue and limit that.
Advantage: You can easily experiment with dropping a random packet in t=
he
queue, instead of the last one, without going through all the calculati=
ons
again.
--=20
We'd like to make a deal with the computer. We promise not to fold,
spindle or mutilate if it will stop asking us to sign our name over
those little holes in the space marked for signature.
--=20
Matthias Urlichs \ noris network GmbH / Xlink-POP N=FCrnberg=
=20
Schleiermacherstra=DFe 12 \ Linux+Internet / EMail: urlichs@nor=
is.de
90491 N=FCrnberg (Germany) \ Consulting+Programming+Networking+etc=
'ing
PGP: 1024/4F578875 1B 89 E2 1C 43 EA 80 44 15 D2 29 CF C6 C7 E0 D=
E
Click <A HREF=3D"http://info.noris.de/~smurf/finger">here</A>. =
42
