[ixpmanager] [Peering matrix] Life time of bgp sessions

[Nick Hilliard (INEX)]

Manel Perez wrote on 16/12/2021 14:31:
>   - increase the sflow rate, but that could be dangerous.

It depends. If your sflow rate sends too few samples, then you lose more 
information.  If it's too high, then two things can happen: either the 
hardware will limit the number of flows exported off the ASIC (usually 
non-uniformly and it may not tell you if it's doing this), or else you 
can overload the switch CPU.

Usually a couple of thousand samples per second is fine on modern 
hardware.  In particular there are plenty of merchant silicon switches 
on the market with quad / six core CPUs, running linux underneath 
everything, i.e. even if the CPU is doing important stuff, there are 
usually cores available for other tasks too, and a good quality scheduler.

Nick