Le mercredi 30 novembre 2011 à 14:36 -0800, Stephen Hemminger a écrit :
> (Almost) nobody uses RED because they can't figure it out.
> According to Wikipedia, VJ says that:
> "there are not one, but two bugs in classic RED."
RED is useful for high throughput routers, I doubt many linux machines
act as such devices.
I was considering adding Adaptative RED (Sally Floyd, Ramakrishna
Gummadi, Scott Shender), August 2001
In this version, maxp is dynamic (from 1% to 50%), and user only have to
setup min_th (target average queue size)
(max_th and wq (burst in linux RED) are automatically setup)
By the way it seems we have a small bug in red_change()
if (skb_queue_empty(&sch->q))
red_end_of_idle_period(&q->parms);
First, if queue is empty, we should call
red_start_of_idle_period(&q->parms);
Second, since we dont use anymore sch->q, but q->qdisc, the test is
meaningless.
Oh well...
[PATCH] sch_red: fix red_change()
Now RED is classful, we must check q->qdisc->q.qlen, and if queue is empty,
we start an idle period, not end it.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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