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

[Robert Raszuk]

Hi Saku,

This is very simple setup:

 linux (.206) ---- LAN---- mx104(.210) ---- p2p---- isp (.209)

Pretty much 1.4 is what is expected. The only place the delay occurs is on
ingress from the ISP to MX104. If I ping MX104 outbound (.210) int I get
0.5 ms.

No worries anyway ... just thought anyone run into this before.

Cheers,
R,



On Mon, Mar 23, 2020 at 2:14 PM Saku Ytti <saku at ytti.fi> wrote:

> 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
>