How does a router or switch decide which processes to give precedence to? For example, if a router is facing a DoS attack (or whatever reason) and because of that, its CPU is pegged, how will it decide whether to process a BGP Hello or to policy-switch a data packet with a QoS marking of EF?
In fact, even during normal operatrion, how are the processes prioritized?
I don't think I have ever read a document that addressed this...
Would love some insight.