[Bloat] [Cerowrt-devel] Invisibility of bufferbloat and its remedies

[Jan Ceuleers]

On 20/06/18 01:41, Jonathan Morton wrote:
>> On 19 Jun, 2018, at 11:34 pm, valdis.kletnieks at vt.edu wrote:
>>
>> Do we have a good cookbook on how to determine the set-rate?
> 
> On DSL, the sync rates in each direction should usually be readable from the modem; they are typically reported on the router's status page.  The advertised rate is less reliable, to say the least.

I'm afraid that my DSL modem doesn't belong to the "usually" case. I
have a BBox3 from Proximus (Belgium). Proximus buys these from two
manufacturers: Technicolor and Sagemcom. I have the Sagemcom variant.

Proximus went out of their way to avoid that end users be able to query
the modem for its connection parameters. There is still an indirect way
to do so in the Sagemcom variant (and so I know that my modem provides
50Mbit/s down and 10Mbit/s up) but for marketing reasons Proxinus would
prefer its users not to know. The reason is that their principal
competitor, cable operator Telenet (owned by Liberty Global) would win
the game based on raw link speed.

So whereas I have access to the information I need to be able to
configure my queues there are others who do not, and it would be good
for a generic method to exist that derives the correct parameters from
measurements.

Kathy put it more succinctly: there is a good case for monitoring.
Question is what to monitor and how to set/modify the qdisc parameters.

Jan