[Codel] [Bloat] Exploring the potential of codel, fq_codel, and qfq

[Jonathan Morton]

There are two goals here. One: provide real feedback to TCPs so that they know when the link is full and thus don't also fill up the buffer constantly. Two: prevent flows from unduly interfering with each other, so they don't have to fill the buffer just to be sure of good throughput. 

What you seem to be saying is that you have a queue full of unresponsive flows that aren't being dropped because they have ECN support and are being marked instead. With FQ, that doesn't matter because other flows can still get through with low latency, and in fq_codel they are treated separately for mark/drop decision purposes. And if the queue really does fill up physically, codel already drops packets at head regardless of ECN capability. 

The key to knowledge is not to rely on others to teach you it. 

On 16 May 2012, at 12:14, Eric Dumazet <eric.dumazet at gmail.com> wrote:

> On Wed, 2012-05-16 at 12:02 +0300, Jonathan Morton wrote:
>> With FQ, I don't see what that would buy you. 
> 
> Sorry I dont understand your point.
>