From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@osdl.org>
Subject: Re: TCP Pacing
Date: Thu, 14 Sep 2006 10:21:55 +0900
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Cc: "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
	Carlo Caini <ccaini@deis.unibo.it>,
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On Wed, 13 Sep 2006 10:18:31 +0200
Daniele Lacamera <root@danielinux.net> wrote:

> On Wednesday 13 September 2006 05:41, Stephen Hemminger wrote:
> > Pacing in itself isn't a bad idea, but:
> <cut>
> > * Since it is most useful over long delay links, maybe it should be a 
> route parameter.
>

Look into rtnetlink and how we keep track of route metrics, and
add a new per route state variable. Need to update iproute2 (ip command)
as well.

> What does this mean? Should I move the sysctl switch elsewhere?
> 
> A new (cleaner) patch follows.
> Thanks to you all for your attention & advices.
> 
> Signed-off by: Daniele Lacamera <root@danielinux.net>

You may also want into look into high resolution timer (hrtimer),
the resolution doesn't get finer than HZ without using -rt patches.
But the ktime interface is cleaner than the normal timer math.