The '5ms lag window by default' is a common misconception.

Codel does not converge to 5ms of delay.  The 5ms (and 100ms) intervals are 
instead measurement windows.  Codel therefore allows for bursts of delay 
that last 100ms, however much delay they add to the stream, but once 'bad 
queue' delay is detected, Codel will remove it entirely.  In most 
situations, that means the actual delay is only a couple of packets.  If 
for some reason more queueing is required to get decent TCP performance, 
Codel will allow that to exist.

fq_codel adds fair queueing, which means the delay is controlled 
individually per flow.

On Tuesday, October 16, 2012 8:46:15 AM UTC+13, Hector Ordorica wrote:
>
> I'm curious if this has ever been tested on an android or otherwise mobile 
> open source device?
>
> In theory it only benefits the user to simply replace pfifo_fast with 
> fq_codel.
>
> However, since codel targets a 5ms lag window by default (and allows for 
> 100ms bursts by default), I think it may need some tuning for a 3G/4G 
> network to allow for more latency.
>
> Anyways, I might play around with this on my tablet at least if compiling 
> the android kernel isn't too difficult.
>
>

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