v1.8.4 — Bounded Async Packet Processing

Overview

This release introduces bounded asynchronous packet processing and explicit pressure visibility.

The packet pipeline is no longer synchronous. Ingress and processing are now decoupled through a bounded queue, making backlog, saturation, and overload observable.

Key Changes

• PacketProcessor is now asynchronous (worker thread + queue)
• Bounded admission (MAX_QUEUE_SIZE = 1024)
• Explicit overload signal: QueueOverflow
• New observability metrics:
  • ingress_packets
  • processed_packets
  • processing_gap
  • drops (by reason)

Why it matters

The system can now:

• accumulate backlog
• expose pressure
• signal overload explicitly

Previously, overload was hidden as callback latency.

Design Notes

• See: docs/v1.8.4-bounded-async-packet-processing.md
• Related: docs/v1.8.2-packet-telemetry.md

Status

This is a foundational architectural change enabling future:

• backpressure policies
• scheduling strategies
• switching logic (v1.9)