Hi,

Just for information, I did a quick test of Wireguard over a 40G
Infiniband network, between two machines with a Xeon E5520.

Using iperf (TCP mode) over the wireguard interface, performance was
around 1.6 Gbit/s.  In bidirectional mode (iperf -d), performance was
700 Mbit/s + 800 Mbit/s.

Note that infiniband has a MTU of 65520 bytes, but Wireguard still selects
a MTU of 1420 bytes for its interface.
After raising the MTU of the wireguard interface to 65450, performance
went up to 7.6 Gbit/s (unidirectional iperf).

Using the Infiniband network directly, iperf's performance is 21.7 Gbit/s
(iperf maxes out the CPU at the receiver, even when using 8 threads).

Hardware used:

- Xeon E5520 @2.27GHz (2 CPUs, 4 cores each)
- Mellanox ConnectX IB 4X QDR MT26428

Versions used:

- Debian jessie
- Linux 3.16.43-2
- Wireguard 0.0.20170421-2
- iperf 2.0.5
- Mellanox ConnectX InfiniBand driver v2.2-1

Baptiste