[j-nsp] Slow RE path 20 x faster then PFE path

[Saku Ytti]

There isn't enough information to answer your question.

But one possible reason is that you're choosing a different path in SW
and HW. Or that the answers are not even coming from host you think
(tshark might add information).

a) is 1.4ms possible in terms of speed-of-light?
b) where are 24ms packets sitting, do you also have longer path
available or are you heavily congested causing massive queueing delay?



On Mon, 23 Mar 2020 at 15:09, Robert Raszuk <robert at raszuk.net> wrote:
>
> Hi,
>
> Would anyone have any idea why IP packets with options are forwarded via
> MX104 20x faster then regular IP packets ?
>
> "fast" PFE path - 24-35 ms
> "slow" RE path - 1-4 ms
>
> Example (I used record route to force IP Options punt to slow path):
>
> rraszuk at cto-lon2:~$ ping 62.189.71.209 -R -v
> PING 62.189.71.209 (62.189.71.209) 56(124) bytes of data.
> 64 bytes from 62.189.71.209: icmp_seq=1 ttl=63 time=1.44 ms
> RR:  69.191.176.206
>         10.249.23.7
>         62.189.71.209
>         10.249.23.7
>         69.191.176.206
>
> 64 bytes from 62.189.71.209: icmp_seq=2 ttl=63 time=1.38 ms
> 64 bytes from 62.189.71.209: icmp_seq=3 ttl=63 time=1.46 ms
> 64 bytes from 62.189.71.209: icmp_seq=4 ttl=63 time=1.41 ms
> 64 bytes from 62.189.71.209: icmp_seq=5 ttl=63 time=1.49 ms
> 64 bytes from 62.189.71.209: icmp_seq=6 ttl=63 time=1.46 ms
> 64 bytes from 62.189.71.209: icmp_seq=8 ttl=63 time=1.52 ms
> 64 bytes from 62.189.71.209: icmp_seq=9 ttl=63 time=2.84 ms
> 64 bytes from 62.189.71.209: icmp_seq=10 ttl=63 time=1.77 ms
> ^C
> --- 62.189.71.209 ping statistics ---
> 10 packets transmitted, 10 received, 0% packet loss, time 9014ms
> rtt min/avg/max/mdev = 1.386/1.892/4.117/0.849 ms
>
> Now I use normal ping running between  62.189.71.209 & 69.191.176.206  in
> "fast" path:
>
> rraszuk at cto-lon2:~$ ping 62.189.71.209 -v
> PING 62.189.71.209 (62.189.71.209) 56(84) bytes of data.
> 64 bytes from 62.189.71.209: icmp_seq=1 ttl=63 time=24.1 ms
> 64 bytes from 62.189.71.209: icmp_seq=2 ttl=63 time=31.5 ms
> 64 bytes from 62.189.71.209: icmp_seq=3 ttl=63 time=24.1 ms
> 64 bytes from 62.189.71.209: icmp_seq=4 ttl=63 time=24.1 ms
> 64 bytes from 62.189.71.209: icmp_seq=5 ttl=63 time=24.0 ms
> 64 bytes from 62.189.71.209: icmp_seq=6 ttl=63 time=24.1 ms
> ^C
> --- 62.189.71.209 ping statistics ---
> 6 packets transmitted, 6 received, 0% packet loss, time 5006ms
> rtt min/avg/max/mdev = 24.097/25.369/31.563/2.774 ms
> rraszuk at cto-lon2:~$
>
> Best,
> R.
> _______________________________________________
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> https://puck.nether.net/mailman/listinfo/juniper-nsp



-- 
  ++ytti