Re: [Bloat] Bufferbloat on 4G Connexion

[David Lang <david@lang.hm>]

[-- Attachment #1: Type: text/plain, Size: 3268 bytes --]

As I understand it, BQL is pretty much a prereq for anything better, if you 
treat a 64 byte packet as if it was a 1500 byte packet, everything else is going 
to fail.

fq_codel is the next stage, it keeps large queues from forming, which makes 
everything work much better.

Cake layers on additional 'fairness' optimizations, but for optimal results, you 
want to have it know the available bandwidth (which is dynamic and changing).

there isn't a single 'do this' right answer, there are a series of 
optimizations. Each additional layer gives better results when tuned, but can
require more tuning, and in many cases, can give worse results than a simpler 
layer if the more complex one is badly tuned.

The most complex part of things is when you try to have one side control the 
queues on the other. If you can say that you will always have active queue 
management on both sides of the link, things get much simpler.

David Lang


On Wed, 23 Oct 2019, erik.taraldsen@telenor.com wrote:

> Date: Wed, 23 Oct 2019 07:28:05 +0000
> From: erik.taraldsen@telenor.com
> To: chromatix99@gmail.com, grobier@icow-systems.com
> Cc: bloat@lists.bufferbloat.net
> Subject: Re: [Bloat] Bufferbloat on 4G Connexion
> 
> If you could influence the 4G vendors to de-bloat their equipment, would you recommend BQL, L4S or codel/cake?
>
>
> -Erik
>
>
> ________________________________________
> Fra: Bloat <bloat-bounces@lists.bufferbloat.net> på vegne av Jonathan Morton <chromatix99@gmail.com>
> Sendt: 22. oktober 2019 23:02
> Til: Guillaume ROBIER
> Kopi: bloat@lists.bufferbloat.net
> Emne: Re: [Bloat] Bufferbloat on 4G Connexion
>
>> On 11 Oct, 2019, at 5:56 pm, Guillaume ROBIER <grobier@icow-systems.com> wrote:
>>
>> I am new to this mailing list and I discovered the bufferbloat in December 
>> 2018. I work on 4G routers and the bufferbloat is very present on this type 
>> of link (4G). I contact you today to find out if people have experimented 
>> with solutions on this type of link or have configuration suggestions, 
>> because the classic fq_codel or piece_of_cake and pie do not allow to fix the 
>> bufferbloat.
>
> This is actually my own situation at home.  My solution is to insert Cake 
> shapers on both upstream *and* downstream directions, and adjust their 
> bandwidth settings according to variations in available 4G speed.  To do this 
> I use an IQrouter, which is basically a TP-Link Archer C7 with custom 
> firmware.
>
> One of the difficulties with 4G in particular is that the link capacity varies 
> a great deal according to both radio propagation conditions (weather, 
> obstructions) and local usage by other subscribers.  That means the right 
> bandwidth setting for the small hours of the night, when nobody is awake, will 
> leave you with a lot of bloat in the evening, when everyone is both awake and 
> home from school/work.  You will need to measure these trends and set up a 
> bandwidth schedule accordingly.
>
> - Jonathan Morton _______________________________________________ Bloat 
> mailing list Bloat@lists.bufferbloat.net 
> https://lists.bufferbloat.net/listinfo/bloat 
> _______________________________________________ Bloat mailing list 
> Bloat@lists.bufferbloat.net https://lists.bufferbloat.net/listinfo/bloat