Single Direction - 7.06 Gbps RX (2.35, 2.35, 1.25, 1.11 Gbps individually), 9.4 Gbps TX (All 2.35 Gbps)
Bidirectionally - 8 Gbps Total, 1.538 Gbps RX & 6.55 Gbps TX (315/1220, 232/2080, 256/1520, 735/1730 Mbps individually)

4x USB NICs on the laptop, 1x Solarflare SFN5122F NIC on the desktop, there were 2 10G switches in between which may have affected the speeds slightly.

Also I can get 4.6 Gbps total (2.3/2.3) bidirectionally on one interface, so I would have expected ~16 Gbps with 4, so that's interesting I guess? My desktop can do 18.6 Gbps total (9.55/9.11) to my server so idk.

Edit: I was using 1500 MTU, I don't feel like testing again with jumbo frames.

[–] AVincentInSpace@pawb.social 2 points 10 months ago* (last edited 10 months ago) (1 children)

Fascinating, especially that the RX direction saw such varied speeds across the various NICs. Guess that switch wasn't too keen on trying to split the packets evenly. Also -- 1.5Gbit RX in bidirectional mode? ...all I can say is yikes.

Very good to know.

@slice@feddit.de -- you were interested in this too

[–] SteveTech@programming.dev 2 points 10 months ago

Guess that switch wasn't too keen on trying to split the packets evenly.

Yeah probably, I was just using one of those cheap 2x 10G + 4x 2.5G switches that ServeTheHome recently did a video on, so I would not be surprised if that was the bottle neck here.

I could maybe try buying a few more SFP+ transceivers and using my more trustworthy switches, but that seems too expensive for a project like this.