[c-nsp] What is the lowest latency switch?

[Jeroen van Ingen]

On 03/17/2011 07:59 AM, Ziv Leyes wrote:
> Even if you had the time to test them, how would you exactly be able to confirm the specs? Do you have a way to measure the<1.9 µsec forwarding latency and confirm it's correct?
>
> Just wondering...
>    
Good question :)

I don't have specialized equipment to verify such low latencies. What 
I'd try would be to connect two servers @ 10 Gbps, have one echo back 
all packets as low in the stack as possible and measure RTT on the 
sender; then compare between back-to-back performance and performance 
with the switch in between (and repeat the tests with other 10G switches).

Not sure how long packet processing takes on an idle Linux box, but it 
would make an interesting experiment (at least to me ;-)).


Regards,
Jeroen