# Complete - m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat

## 완료 일시

2026-06-06T03:38:31Z

## 요약

Dart TCP no-delay, per-packet flush 제거, heartbeat interval/wait 0 disabled semantics, focused stress/performance evidence를 1회 리뷰 루프로 확인했고 최종 판정은 PASS다.

## 루프 이력

| Plan | Review | Verdict | 메모 |
|------|--------|---------|------|
| `plan_cloud_G07_0.log` | `code_review_cloud_G07_0.log` | PASS | no-delay/flush/heartbeat 변경과 성능 hard gate 증거가 계획 범위를 충족함 |

## 구현/정리 내용

- `dart/lib/src/protobuf_client.dart`에서 TCP socket no-delay를 생성자 경로에 적용하고 per-packet `flush()` await를 제거했다.
- `dart/lib/src/heartbeat_mixin.dart`와 `dart/bench/stress.dart`에서 heartbeat interval 또는 wait 0을 disabled semantics로 정리했다.
- `dart/test/socket_test.dart`에 heartbeat disabled 유지/송수신 회귀 테스트가 추가됐다.

## 최종 검증

- `cd dart && dart test test/socket_test.dart -r expanded` - PASS; 리뷰 중 재실행 결과 41 tests all passed.
- `cd dart && dart test test/communicator_test.dart -r expanded` - PASS; 리뷰 중 재실행 결과 21 tests all passed.
- `cd dart && dart analyze lib bench test` - PASS with existing info; `heartbeat_mixin.dart:13:16 annotate_overrides` info 1건은 기존 추상 선언 이슈이며 이번 변경 차단 아님.
- `cd dart && dart compile js test/browser_ws_import_compile.dart -o /tmp/proto_socket_browser_ws_import_compile.js` - PASS; 리뷰 중 재실행 결과 JavaScript compile 성공.
- `bash agent-ops/skills/project/run-proto-socket-test-matrix/scripts/run_stress.sh --quick --lang dart --transport tcp --profile roundtrip,burst,sustained` - PASS; evidence=`agent-test/runs/20260606-031314-proto-socket-stress-quick.md`.
- `bash agent-ops/skills/project/run-proto-socket-test-matrix/scripts/run_performance.sh --quick` - PASS; evidence=`agent-test/runs/20260606-031336-proto-socket-performance-quick.md`.

## Roadmap Completion

- Milestone: `agent-roadmap/milestones/performance-hotspot-optimization.md`
- Completed task ids:
  - `dart-tcp-fixed-latency`: PASS; evidence=`agent-task/archive/2026/06/m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat/plan_cloud_G07_0.log`, `agent-task/archive/2026/06/m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat/code_review_cloud_G07_0.log`; verification=`agent-test/runs/20260606-031314-proto-socket-stress-quick.md`, `agent-test/runs/20260606-031336-proto-socket-performance-quick.md`
  - `dart-tcp-burst-sustained`: PASS; evidence=`agent-task/archive/2026/06/m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat/plan_cloud_G07_0.log`, `agent-task/archive/2026/06/m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat/code_review_cloud_G07_0.log`; verification=`agent-test/runs/20260606-031314-proto-socket-stress-quick.md`, `agent-test/runs/20260606-031336-proto-socket-performance-quick.md`
  - `dart-heartbeat-cost`: PASS; evidence=`agent-task/archive/2026/06/m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat/plan_cloud_G07_0.log`, `agent-task/archive/2026/06/m-performance-hotspot-optimization/09_dart_tcp_latency_heartbeat/code_review_cloud_G07_0.log`; verification=`cd dart && dart test test/socket_test.dart -r expanded`, `agent-test/runs/20260606-031314-proto-socket-stress-quick.md`
- Not completed task ids: 없음

## 잔여 Nit

- 없음

## 후속 작업

- 없음
