General • Re: How good is PCC with a 1:2 ratio

Is the traffic VPNs/tunnels/etc – e.g. are connections going to small set of destinations on WANs? Or, is the there a lot of general internet traffic flowing (e.g. lots of connections with many different destination IPs). Basically be good to know if the issue is hashing not creating a suitably random distribution... Or... if there is some config issue elsewhere.

I get the same result even when there is no other network traffic. So the problem seem to be with the hash distribution. As for any other configuration issue, I'm reviewing it constantly in search for any problem.

One thing I may try next weekend is to use a very simple config and see if the issue persists.

I usually use ECMP, which round-robins connections (e.g. 2 routes to ISP1, 1 router to ISP, all with same distance= to get a 2:1 ratio)... but PCC should work, but the math will always calculate same dst wan for particular app/service is why I ask about #connection and concerned about hashing. While in ECMP: more connections, more randomness.

If I understand ECMP correctly it will use a "per-src-dst-address combination load balancing" so one will never be able to fully use all the bandwidth for a multiple connections download. Not really easy to accomplish at such speeds, but if downloading from a CDN that is close it may work. With PCC, having the (random) port in the equation may alleviate the issue.

Statistics: Posted by arnaldo — Mon Feb 05, 2024 8:50 pm

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