[Jool-list] Default pool4 hashing does not work well with some video CDNs

[Alberto Leiva]

Actually, that's a great idea. I'll try implementing it over the weekend.

On Thu, Apr 20, 2023 at 10:57 AM Ondřej Caletka <ondrej at caletka.cz> wrote:
>
> On 20/04/2023 17:07, Alberto Leiva wrote:
> >> Or perhaps even change the pool4
> >> allocation algorithm so that it tries to stick to one IPv4 address for
> >> one source address and just randomize ports used.
> > But how is this different from f-args 8?
>
> If I understand the docs correctly, algorithm of Jool treats pool4 as a
> flat list of (IPv4, port) tuples. The F-function is run and its result
> chooses one of the tuples. If that one is in use, a possibly CPU-intense
> algorithm is run to find a free tuple adjacent to the one chosen by F.
>
> That is, with f-args=8, every session originated from the same IPv6
> source address will always try to select one particular tuple. So every
> second and further session from the same host will trigger this
> collision resolution process.
>
> What I would like to see instead would be to use F with f-args=8 only to
> select IPv4 address. Once it is selected, another F could be run, this
> time with f-args=15 (or 7) to select a port within that IPv4 address.
> This way it would be guaranteed that one IPv6 address is always masked
> behind one IPv4 address and at the same time there would be less collisions.
>
> But maybe I'm just too scared of the collision resolving algorithm :)
>
> --
> Cheers,
>
> Ondřej Caletka