Mesa - Ethernet v's PCI/e

Takes me back! I've never really paid attention to the rapids on my machine but having rewatched the video, it is pretty quick!

I'm running 5x microstepping and 3:1 on the NEMA 23 X axis and 5:1 on the Nema 34 Y axis gantry ends so the step rate is pretty high at full speed. There are a lot of hardware and timing limitations that usually prevent the full 10 Mhz stepgen frequency being used. I think from memory my max speed is about 95 kHz.

The reason the Mesa hardware gets such high performance is that it has a hardware step generator. So Linuxcnc tells it to generate step pulses at a given frequency and it does that until LinuxCNC tells it to change. LinuxCNC can change the commanded frequency 1000 times a second so it becomes a very responsive system.

Hello.
If we suppose that computer has very low jitter for example the jitter has the orange pi5.
What is the best servo thread frequency
can achieve an ethernet and a pci-e mesa card? What are the limitations of eth and pci-e buses?
For stepper systems 1khz is enough
but what about pwm like H-bridge or analog speed servos with encoders feedback to linuxcnc that needs high speed/accelaration?
1khz in this case is enough or 4-8khz has improved performance?