On Tue Sep 16, 2025 at 03:01:33PM +0200, Rafael Sadowski wrote:
> Hi all!
>
> WireGuard shows severe performance degradation (95% bandwidth
> loss) on Intel 10Gb interfaces compared to direct connections,
> with significant packet loss patterns.
>
> Performance Comparison:
>
> ServerA (Chicago) - Intel 10Gb interface (ix0)
> ServerB (Atlanta) - Intel 10Gb interface (ix3)
>
> - Direct connection (iperf): 66.8 Mbps
> - WireGuard tunnel (iperf): 3.3 Mbps
> - Performance loss: 95%
>
> The physical Intel interface (ix3) shows 149426 output failures:
>
> ix3 1500 <Link> f8:f2:1e:3c:9c:09 195418012 0 144748154 149426
> 0
>
> suggesting hardware/driver level problems that worsen with
> WireGuard traffic processing?
>
> Are there known compatibility issues between ix(4) driver and
> WireGuard packet processing?
>
> Could the bridge configuration (veb0 + vport0) be contributing to
> the packet loss patterns?
>
> Any guidance on debugging approaches or known workarounds would be
> greatly appreciated. I'm happy to provide additional data.
>
> Data from ServerB
>
This ix3+veb0+vport0 +wg0 causes the problems we see under "Intel 82599".
$ dmesg | grep ix3
ix3 at pci5 dev 0 function 1 "Intel 82599" rev 0x01, msix, 16 queues, address
f8:f2:1e:3c:9c:09
$ ifconfig ix3
ix3: flags=8b43<UP,BROADCAST,RUNNING,PROMISC,ALLMULTI,SIMPLEX,MULTICAST> mtu
1500
lladdr f8:f2:1e:3c:9c:09
index 4 priority 0 llprio 3
media: Ethernet 10GSFP+Cu (10GSFP+Cu full-duplex,rxpause,txpause)
status: active
I found two different servers with the same Intel 82599"
dmesg | grep ix0
ix0 at pci3 dev 0 function 0 "Intel 82599" rev 0x01, msix, 1 queue, address
84:2b:2b:de:d2:cc
ix0 at pci3 dev 0 function 0 "Intel 82599" rev 0x01, msix, 1 queue, address
84:2b:2b:de:d2:cc
ix0 at pci3 dev 0 function 0 "Intel 82599" rev 0x01, msix, 16 queues, address
84:2b:2b:de:d2:cc
ix0 at pci3 dev 0 function 0 "Intel 82599" rev 0x01, msix, 16 queues, address
84:2b:2b:de:d2:cc
ix0 at pci3 dev 0 function 0 "Intel 82599" rev 0x01, msix, 16 queues, address
84:2b:2b:de:d2:cc
ifconfig ix0
ix0: flags=8b43<UP,BROADCAST,RUNNING,PROMISC,ALLMULTI,SIMPLEX,MULTICAST> mtu
1500
lladdr 84:2b:2b:de:d2:cc
index 1 priority 0 llprio 3
media: Ethernet autoselect (10GbaseKR full-duplex)
status: active
With this I see 132 Mbits/sec via wg0. What I notice: media is
different and there are 5 lines in the dmesg. Maybe that means something.
