performance query

[Kalin KOZHUHAROV]

On Fri, Mar 1, 2019 at 11:11 AM Scott Lipcon <slipcon at gmail.com> wrote:
>
> I've been experimenting a bit with Wireguard on several ubuntu systems, and am not seeing the performance I'd expect based on the numbers at https://www.wireguard.com/performance/
>
> I'm wondering if there is a configuration setting i'm missing or any better way to debug this.
>
> Testing between two locations - both have nominally 1Gbit internet connections from the same provider.
>
> At location A:
> 1) Ubuntu 18.04 "server" - i7-4790K CPU @ 4.00GHz
> 2) Ubuntu 16.04 client - i5-3470 CPU @ 3.20GHz
>
> At location B:
> 3) Ubuntu 18.04 client - Celeron N2808  @ 1.58GHz
> 4) Ubuntu 18.04 client - Virtual Machine - Xeon(R) Gold 6126 CPU @ 2.60GHz
>
>
> Using iperf3 for all tests, with 8 threads, but that doesn't seem to matter significantly.
>
> Between 1 & 2, via gigabit LAN - 940 Mbit/sec.
> Between 1 & 2, via WireGuard - 585 Mbit/sec
> - I might have expected a bit higher, but this is certainly acceptable.
>
> Between 3 and 1, direct iperf3 - 580 Mbit/sec
> Between 3 and 1, WireGuard - 73 Mbit/sec
>
> At this point I was guessing WireGuard was CPU limited on this little Celeron, so I set up the Xeon VM (#4):
>
> Between 4 and 1, direct iperf3 - ~600 Mbit/sec
> Between 4 and 1, WireGuard - 80 Mbit/sec
>
> In other words, the much faster VM is only a tiny bit faster that the celeron.
>
> Any suggestions?

A lot can go wrong speed-wise "on the Internet"...

What sits in between those hosts that you have control of (routers,
switches, firewalls...)?
IPv6 involved at all?
ISP having throttling policy for "UDP we don't understand"?
Play with the MTU, you might be hitting some fragmentation issues that
a weak router is not handling fast enough.
Play with Wireshark (new 3.0 even has support for wireguard
protocol!), capture some traffic, look for any transmission errors.

Cheers,
Kalin.