Interrupt Moderation and Busy Polling
NIC interrupt moderation waits for more packets before notifying the CPU. Busy polling looks for them proactively. Both trade CPU consumption for batching and response time.
Planned model
Deliver adjustable packet bursts under immediate interrupts, coalescing, adaptive moderation, and busy polling. Plot notification count and latency distribution.
Questions
- What does a coalescing timer delay?
- How does packet rate change the best policy?
- Which CPU performs the poll and what else can run there?
Exercise
Choose an interrupt and polling policy for quiet periods punctuated by high-value bursts.