Re: Ping Spikes

On 08/06/25 09:44, Jon Higgs wrote:
> I've just checked my system again because I remember seeing something
> similar, but never really bothered to get to the bottom of it.
>
> I have an USG-PRO-4 running OpenBSD 7.7 (octeon) as my firewall. I have
> a stable ping time to the internet from its console:
>
> --- 8.8.8.8 ping statistics ---
> 28 packets transmitted, 28 packets received, 0.0% packet loss
> round-trip min/avg/max/std-dev = 1.277/1.407/2.327/0.227 ms
>
> But when I ping through that router, the ping times are unstable:
>
> PING 8.8.8.8 (8.8.8.8): 56 data bytes
> 64 bytes from 8.8.8.8: icmp_seq=0 ttl=119 time=3.467 ms
> 64 bytes from 8.8.8.8: icmp_seq=1 ttl=119 time=4.557 ms
> 64 bytes from 8.8.8.8: icmp_seq=2 ttl=119 time=3.062 ms
> 64 bytes from 8.8.8.8: icmp_seq=3 ttl=119 time=2.789 ms
> 64 bytes from 8.8.8.8: icmp_seq=4 ttl=119 time=2.535 ms
> 64 bytes from 8.8.8.8: icmp_seq=5 ttl=119 time=15.862 ms
> 64 bytes from 8.8.8.8: icmp_seq=6 ttl=119 time=2.412 ms
> 64 bytes from 8.8.8.8: icmp_seq=7 ttl=119 time=4.835 ms
> 64 bytes from 8.8.8.8: icmp_seq=8 ttl=119 time=3.064 ms
> 64 bytes from 8.8.8.8: icmp_seq=9 ttl=119 time=6.468 ms
> 64 bytes from 8.8.8.8: icmp_seq=10 ttl=119 time=2.968 ms
> 64 bytes from 8.8.8.8: icmp_seq=11 ttl=119 time=2.670 ms
> 64 bytes from 8.8.8.8: icmp_seq=12 ttl=119 time=3.017 ms
> 64 bytes from 8.8.8.8: icmp_seq=13 ttl=119 time=3.374 ms
> 64 bytes from 8.8.8.8: icmp_seq=14 ttl=119 time=3.082 ms
> 64 bytes from 8.8.8.8: icmp_seq=15 ttl=119 time=8.898 ms
> 64 bytes from 8.8.8.8: icmp_seq=16 ttl=119 time=3.568 ms
> 64 bytes from 8.8.8.8: icmp_seq=17 ttl=119 time=2.793 ms
> 64 bytes from 8.8.8.8: icmp_seq=18 ttl=119 time=14.768 ms
> 64 bytes from 8.8.8.8: icmp_seq=19 ttl=119 time=10.134 ms
> 64 bytes from 8.8.8.8: icmp_seq=20 ttl=119 time=2.249 ms
> 64 bytes from 8.8.8.8: icmp_seq=21 ttl=119 time=2.403 ms
> ^C
> --- 8.8.8.8 ping statistics ---
> 22 packets transmitted, 22 packets received, 0.0% packet loss
> round-trip min/avg/max/stddev = 2.249/4.953/15.862/3.849 ms
>
> That ping was conducted from a Mac connected to the network over
> Ethernet. The situation is similar regardless which host or operating
> system I ping from.
>
> The ping times between nodes on the same network segment is fast so the
> latency isn't introduced by my switch.
>
> Cheers,
>
> Jon
>

I had a thought that perhaps the latency was coming from NAT. I ran
another test between two VLANs connected together by the same router.
This route doesn't have NAT. It's an improvement but I still don't think
it's working as well as it should:

PING moth.i.altos (172.16.0.130): 56 data bytes
64 bytes from 172.16.0.130: icmp_seq=0 ttl=255 time=2.131 ms
64 bytes from 172.16.0.130: icmp_seq=1 ttl=255 time=2.518 ms
64 bytes from 172.16.0.130: icmp_seq=2 ttl=255 time=1.338 ms
64 bytes from 172.16.0.130: icmp_seq=3 ttl=255 time=1.673 ms
64 bytes from 172.16.0.130: icmp_seq=4 ttl=255 time=1.255 ms
64 bytes from 172.16.0.130: icmp_seq=5 ttl=255 time=1.221 ms
64 bytes from 172.16.0.130: icmp_seq=6 ttl=255 time=1.372 ms
64 bytes from 172.16.0.130: icmp_seq=7 ttl=255 time=1.306 ms
64 bytes from 172.16.0.130: icmp_seq=8 ttl=255 time=1.304 ms
64 bytes from 172.16.0.130: icmp_seq=9 ttl=255 time=1.318 ms
64 bytes from 172.16.0.130: icmp_seq=10 ttl=255 time=2.724 ms
64 bytes from 172.16.0.130: icmp_seq=11 ttl=255 time=7.588 ms
64 bytes from 172.16.0.130: icmp_seq=12 ttl=255 time=2.636 ms
64 bytes from 172.16.0.130: icmp_seq=13 ttl=255 time=1.286 ms
64 bytes from 172.16.0.130: icmp_seq=14 ttl=255 time=1.404 ms
64 bytes from 172.16.0.130: icmp_seq=15 ttl=255 time=1.187 ms
64 bytes from 172.16.0.130: icmp_seq=16 ttl=255 time=1.446 ms
64 bytes from 172.16.0.130: icmp_seq=17 ttl=255 time=3.033 ms
64 bytes from 172.16.0.130: icmp_seq=18 ttl=255 time=1.308 ms
64 bytes from 172.16.0.130: icmp_seq=19 ttl=255 time=1.230 ms
64 bytes from 172.16.0.130: icmp_seq=20 ttl=255 time=4.077 ms
64 bytes from 172.16.0.130: icmp_seq=21 ttl=255 time=1.279 ms
64 bytes from 172.16.0.130: icmp_seq=22 ttl=255 time=1.369 ms
64 bytes from 172.16.0.130: icmp_seq=23 ttl=255 time=1.099 ms
64 bytes from 172.16.0.130: icmp_seq=24 ttl=255 time=0.968 ms
64 bytes from 172.16.0.130: icmp_seq=25 ttl=255 time=1.030 ms
64 bytes from 172.16.0.130: icmp_seq=26 ttl=255 time=1.322 ms
64 bytes from 172.16.0.130: icmp_seq=27 ttl=255 time=8.230 ms
64 bytes from 172.16.0.130: icmp_seq=28 ttl=255 time=6.645 ms
64 bytes from 172.16.0.130: icmp_seq=29 ttl=255 time=1.207 ms
64 bytes from 172.16.0.130: icmp_seq=30 ttl=255 time=1.269 ms
64 bytes from 172.16.0.130: icmp_seq=31 ttl=255 time=6.929 ms
64 bytes from 172.16.0.130: icmp_seq=32 ttl=255 time=5.247 ms
64 bytes from 172.16.0.130: icmp_seq=33 ttl=255 time=1.580 ms
64 bytes from 172.16.0.130: icmp_seq=34 ttl=255 time=6.042 ms
64 bytes from 172.16.0.130: icmp_seq=35 ttl=255 time=2.017 ms
64 bytes from 172.16.0.130: icmp_seq=36 ttl=255 time=10.905 ms
64 bytes from 172.16.0.130: icmp_seq=37 ttl=255 time=4.784 ms
64 bytes from 172.16.0.130: icmp_seq=38 ttl=255 time=1.876 ms
64 bytes from 172.16.0.130: icmp_seq=39 ttl=255 time=6.749 ms
64 bytes from 172.16.0.130: icmp_seq=40 ttl=255 time=1.379 ms
64 bytes from 172.16.0.130: icmp_seq=41 ttl=255 time=1.389 ms
64 bytes from 172.16.0.130: icmp_seq=42 ttl=255 time=1.672 ms
^C
--- moth.i.altos ping statistics ---
43 packets transmitted, 43 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.968/2.752/10.905/2.399 ms

I double-checked by connecting directly to that VLAN so that my pings
weren't routed through the route. The ping times improved but there were
still a few spikes.

--- moth.i.altos ping statistics ---
34 packets transmitted, 34 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.593/1.027/1.564/0.152 ms

The target (moth) is running OpenBSD 7.7 on a Xeon E3-1271 v3.

--
Jon