Cross post from Reddit. Hopefully someone can help here. Original Reddit post: https://www.reddit.com/r/zerotier/comments/wuqumy/zerotier_multipath_not_using_full_bandwidth/
I have a linux vm setup with 2 internet links (1Gb/50Mb Cable modem and 2Gb/200Mb FTTH). I have Zerotier installed on it and box in a datacenter (2Gb link on it) and have set Zerotier to use balance-aware (also tried balance-rr and balance-xor) and, although it does seem to be using both links for balance-aware and balance-rr, it does not seem to be able to use the full bandwith of the links… it is topping out at around 300mb/s down and 150mb/s up. the box in the house has 8 cores (Xeon Scalable V1) and 16Gb RAM. the box upstream has 4 cores (Xeon E3 V2) and 8GB RAM.
What am i missing? Any performance tuning stuff i can do to make things faster?
[EDIT] 2 things to clarify: 1: box in house is running Ubuntu 22.04. Box in the cloud is running Debian (latest). also, neither box is behind a firewall.
[EDIT2] Bit more digging. Seems that when i am downloading at a high speed (managed to get around 550Mb/s just now) the upstream server (a slightly different one, a Skylake 2 cores @ 2Gz) is running 70-90% CPU usage (one core is hitting 100%, the other around 70-80%). The home machine has 8 cores assigned, so it seems to be doing a bit better…
Is there anything at a config level i can tweak to make this work faster?