Comment by sgarland
5 months ago
If nothing else, handling interrupts from the NIC to pull packets out of its receive buffer, though that should be usually be isolated to a couple of cores.
Also, re: I/O, the CPU usually also has to handle interrupts there, as well as whatever the application might be doing either that I/O.
> If nothing else, handling interrupts from the NIC to pull packets out of its receive buffer,
Interrupts? Interrupts? We don't need no stinking interrupts! https://docs.kernel.org/networking/napi.html#poll