CoDel AQM discussions
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From: Jonathan Morton <chromatix99@gmail.com>
To: "Toke Høiland-Jørgensen" <toke@toke.dk>
Cc: cake@lists.bufferbloat.net,
	"codel@lists.bufferbloat.net" <codel@lists.bufferbloat.net>
Subject: Re: [Codel] [Cake]  hard limit codel
Date: Thu, 16 Apr 2015 15:00:21 +0300	[thread overview]
Message-ID: <91CCD5F5-5F5D-435D-9FD1-77BBEEC1E84E@gmail.com> (raw)
In-Reply-To: <87twwg5m1u.fsf@toke.dk>


> On 16 Apr, 2015, at 14:50, Toke Høiland-Jørgensen <toke@toke.dk> wrote:
> 
> I'll add, though, that I have seen the sentiment expressed here ("we
> need to limit the max delay of CoDel") in other contexts. And, well,
> delay spikes *is* a problem!

Yes, they are.

But in general AQM can’t be used to solve that problem without also suffering poor throughput; combining AQM with FQ *does* solve it.  Just like FQ is unfair to single flows competing against a swarm, but classifying the swarm traffic into a separate traffic class fixes that problem too.

Which of course is why cake uses AQM, FQ *and* Diffserv, all at once.

The linked paper didn’t measure HLC against fq_codel, even though they mention fq_codel.  That’s a major shortcoming.

 - Jonathan Morton


  reply	other threads:[~2015-04-16 12:00 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-16  3:23 [Codel] " Dave Taht
2015-04-16  4:16 ` Kathleen Nichols
2015-04-16  5:06   ` Eric Dumazet
2015-04-16  4:25 ` Rich Brown
2015-04-16 11:50   ` [Codel] [Cake] " Toke Høiland-Jørgensen
2015-04-16 12:00     ` Jonathan Morton [this message]
2015-04-16 12:10       ` Andrew McGregor
2015-04-16 14:47       ` Kathleen Nichols
2015-04-16 15:02         ` Toke Høiland-Jørgensen
2015-04-16 16:04           ` Kathleen Nichols

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