How to improve Wireguard speed?

[Janne Johansson]

Den ons 1 juni 2022 kl 09:49 skrev Houman <houmie at gmail.com>:
> Hello,
> I'm compiling the latest stable Wireguard on Debian 11.
> git clone https://git.zx2c4.com/wireguard-tools
> make -C wireguard-tools/src -j$(nproc)
> sudo make -C wireguard-tools/src install
>
> However the speed is not that impressive.  I have a VPS with 4 vCores
> and 8 GB RAM on 1 Gbps network.  The VPS is located in London and so
> am I.
>
> With wireguard enabled I get 117 Mbps
> Without wireguard I get 506 Mbps
>
> That's a drop of 75%. What are the factors to improve the download rate?

That seems like very poor values, I would make two tests, one local to
the VPS and one test local to the other end (which you left out of the
description) and see which one is the limiting box. People (including
me) have easily gotten speeds at 1-2 gigabit on 10GE networked
computers and VPSes and several gigabits on loopbacks, so the fault is
not simply using wireguard.

If you check the results of the nightly builds for x86_64 at
https://www.wireguard.com/build-status/ you find several iperf3 runs
that end up over 2-3 Gbit/s when a box is talking "to itself" so it's
not the crypto or the tunnel that prevents you from filling up the
gigabit link. Perhaps the VPS isn't giving you a lot of cpu? Perhaps
the test reacts poorly to the lowered MTU for using (any) tunnel in
between?

-- 
May the most significant bit of your life be positive.