Re: [PATCH RFC 0/2] Better throughput estimation on half duplex interfaces

[Marek Lindner <mareklindner@neomailbox.ch>]

On Thursday, 28 September 2023 14:39:34 CEST Remi Pommarel wrote:
> Then Orig1 first adapts the Orig0 OGM throughput to T01/2 then forwards it
> on same interface it received it. Orig2 receives it and first thing Orig2
> does is checking if T12 is lower than the received OGM throughput (i.e.
> T01/2), and if that is the case T12 is considered to be the new end-to-end
> path throughput.
> 
> The first issue I see here is that Orig2 does not know the path to reach
> Orig0 has to get half duplex penalty because it is forwarded on same WiFi
> interface on Orig1, only Orig1 knows that. Thus if T12 is lower that T01/2,
> T12 will be chosen as the Orig2 to Orig0 path throughput (i.e PT02) and the
> half duplex penalty is lost.

I am not quite following where you see the problem. 

The half duplex / store & forward penalty is for situations in which batman-
adv has to forward packets from an interface to another. In your scenario that 
only is Orig1.

Why should Orig2 need to care whether Orig1 does store & forward or not?

If the direct path from Orig0 to Orig2 is better than the path over Orig1 the 
metric should reflect that.

Maybe you can add throughput metric values to your example and then expand on 
what you find problematic?

Cheers,
Marek