NIC Queues, RSS, and Flow Steering
Modern NICs expose multiple queues so packet processing can be distributed, but queue, interrupt, CPU, and application ownership must align.
Planned model
Hash flows into receive queues and steer queues to CPUs. Display reordering risks, hot flows, interrupt affinity, cache locality, and NUMA placement.
Questions
- Which packet fields feed the receive-side scaling hash?
- How can one heavy flow dominate a queue?
- Where should queue memory and its consumer thread reside?
Exercise
Map eight receive queues to a two-socket CPU topology and explain how application flow ownership follows the mapping.