mesa setup 7i98 with 7i88, 7i89, 7i74, 7i70, 7i72 & 7i73

Ping is around 0.1ms. Max latency on this computer is around 20µs for the servo-thread which is truly quite much.
What latency would be the limit for this kind of setup?

20 usec latency is fine

It does seem like a dropped packet issue

What is the host Ethernet chip?

Intel chips need to have RX IRQ colalescing turned off

(man hm2_eth)

I kept the latency test running during browsing and the latency does get higher. I have also seen 60µs. I guess more would also be possible. Not sure when this could become a problem.

I have two Reaktek network chipsets in this computer. Not sure which is actually connected to the 7i80:
RTL810xE/RTL8169

I still set the irq-thingie and nothing really changed. I have attached another output file. After enough tries it seems to register but this it not a solution.
I wonder if my diy-flat-cables could be a problem? Are shielded-25pin cables necessary?

best regards,
Alex
 

Flat cable could be an issue (it was in the past before digital filtering was added to the UART
RX) But if you have a current bitfile (newer than a couple years old) even a 10 foot flat cable should be OK

IRQ coalescing does not affect the RealTek driver

@tommylight:
I didn't get smarter after disconnecting single devices. The problem seems to be quite random to me. I just ordered a new set of cables just to make sure (RJ45 and 25pin).

@PCW: You have compiled my bitfile in March, so it should be fine... but anyways I will just make sure it is not about cheap cables. I will know more in a week.

I would try another PC host as it still looks like a global problem of some kind
(like dropped packets)

Found the problem before my new cables arrived. I couldn't use another pc but I just swapped ethernet-ports. Now I am using the on-board lan for 7i80 and the pci-ethernet card for lan/internet.

Tada: connection is stable and mesa cards work great ).
Thank you very much for your support!

Now I am already struggling with encoder input configuration but I'll ask after I have checked my hardware - maybe the encoders are the problem.

Thanks & best regards,
Alex