- Preserve and replay subscription ref counts across address space rebuilds to prevent MXAccess subscription leaks
- Mark read timeouts and write failures as unsuccessful in PerformanceMetrics for accurate health reporting
- Add deferred MxAccess reconnect path when initial connection fails at startup
- Update code review document with verified completions and new findings
- Add covering tests for all fixes
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
9 tests verifying server handles multiple simultaneous OPC UA clients:
Subscription sync:
- 3 clients subscribe to same tag, all receive data changes
- Client disconnect doesn't affect other clients' subscriptions
- Client unsubscribe doesn't affect other clients' subscriptions
- Clients subscribing to different tags receive only their own data
Concurrency:
- 5 clients browse simultaneously, all get identical results
- 5 clients browse different nodes concurrently, all succeed
- 4 clients browse+subscribe simultaneously, no interference
- 3 clients subscribe+browse concurrently, no deadlock (timeout-guarded)
- Rapid connect/disconnect cycles (10x), server stays stable
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
