koriweb
d8a80f6272
이름만 다른(표기 변형) [[위키링크]]를 대상 문서의 canonical 제목으로 치환해 끊겼던 1,200개 링크를 연결. 제목/파일명 정규화 일치만 적용하고 별칭 매칭은 과병합 위험으로 제외(애매성 가드). 원본은 _link_reconcile_backup/ 에 백업. 도구: Datacollect/scripts/link_reconcile_apply.mjs Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
141 lines
4.9 KiB
Markdown
141 lines
4.9 KiB
Markdown
---
|
|
id: wiki-2026-0508-orinoco
|
|
title: Orinoco (V8 GC project)
|
|
category: 10_Wiki/Topics
|
|
status: verified
|
|
canonical_id: self
|
|
aliases: [V8 Orinoco, Orinoco GC, Concurrent V8 GC]
|
|
duplicate_of: none
|
|
source_trust_level: A
|
|
confidence_score: 0.9
|
|
verification_status: applied
|
|
tags: [v8, gc, performance, concurrent-marking, runtime]
|
|
raw_sources: []
|
|
last_reinforced: 2026-05-10
|
|
github_commit: pending
|
|
tech_stack:
|
|
language: cpp
|
|
framework: v8
|
|
---
|
|
|
|
# Orinoco
|
|
|
|
## 매 한 줄
|
|
> **"매 V8의 GC를 stop-the-world에서 incremental · concurrent · parallel multi-threaded GC로 전환한 multi-year 프로젝트."**. 2016년 시작, 2017-2019 Concurrent Marking · Parallel Scavenger · Lazy Sweeping 차례 도입. 2026 현재 V8 13.x base GC architecture가 Orinoco — pause time을 100ms+ → <1ms로 감소.
|
|
|
|
## 매 핵심
|
|
|
|
### 매 핵심 기법
|
|
- **Parallel Scavenger** (Young Gen): 매 multiple worker가 semi-space copy 병렬화.
|
|
- **Concurrent Marking** (Old Gen): 매 worker thread가 mutator와 병행 mark — main thread는 거의 미 pause.
|
|
- **Incremental Marking**: 매 mark phase를 여러 작은 chunk로 나눔.
|
|
- **Parallel/Concurrent Compaction**: page별 evacuation 병렬화.
|
|
- **Lazy Sweeping**: 매 sweep을 allocation 시점까지 지연.
|
|
- **Black Allocation**: 매 marking 중 새 alloc은 black (skip).
|
|
|
|
### 매 write barrier 역할
|
|
- 매 mutator가 마크된 object → 비마크 object 참조 추가 시 dirty card 표시.
|
|
- 매 concurrent marker가 stale graph 처리.
|
|
|
|
### 매 응용
|
|
1. Chrome — main thread jank 감소, smooth 60fps scroll.
|
|
2. Node.js — large heap server에서 long pause 제거.
|
|
3. Electron/VSCode — GUI responsiveness 유지.
|
|
|
|
## 💻 패턴
|
|
|
|
### Orinoco effect 측정 (Node.js)
|
|
```bash
|
|
# Major GC pause 분포
|
|
node --trace-gc --trace-gc-verbose app.js 2>&1 \
|
|
| grep "Mark-" | awk '{print $5}' \
|
|
| sort -n | uniq -c
|
|
# 2026 V8: 대부분 < 1ms, occasional 5ms
|
|
```
|
|
|
|
### Disable concurrent marking (compare)
|
|
```bash
|
|
node --no-concurrent-marking --trace-gc app.js
|
|
# pause time 명백히 증가 (10-50ms 종종)
|
|
```
|
|
|
|
### Per-isolate GC stats
|
|
```javascript
|
|
import { getHeapStatistics } from 'node:v8';
|
|
|
|
const before = getHeapStatistics();
|
|
heavyWorkload();
|
|
const after = getHeapStatistics();
|
|
console.log('major_gc count:', after.number_of_native_contexts);
|
|
console.log('used:', (after.used_heap_size - before.used_heap_size) / 1e6, 'MB');
|
|
```
|
|
|
|
### Performance.measureUserAgentSpecificMemory (Chrome)
|
|
```javascript
|
|
// In Chrome with COOP+COEP
|
|
if (performance.measureUserAgentSpecificMemory) {
|
|
const result = await performance.measureUserAgentSpecificMemory();
|
|
console.log(result.bytes, result.breakdown);
|
|
}
|
|
```
|
|
|
|
### Reduce concurrent-marking pressure
|
|
```javascript
|
|
// Avoid: huge graph mutation in tight loop
|
|
function reseat(arr, n) {
|
|
for (let i = 0; i < n; i++) arr[i] = { ref: arr[(i+1) % n] };
|
|
// many write barriers → marker work spike
|
|
}
|
|
// Prefer: build once, freeze
|
|
const frozen = Object.freeze(buildGraph());
|
|
```
|
|
|
|
### Inspect GC marking phase via perf_hooks
|
|
```javascript
|
|
import { PerformanceObserver } from 'node:perf_hooks';
|
|
|
|
const obs = new PerformanceObserver(list => {
|
|
for (const e of list.getEntriesByType('gc')) {
|
|
if (e.detail.kind === 2 /* MARK_SWEEP_COMPACT */)
|
|
console.log('major GC:', e.duration.toFixed(2), 'ms');
|
|
}
|
|
});
|
|
obs.observe({ entryTypes: ['gc'] });
|
|
```
|
|
|
|
## 매 결정 기준
|
|
| 상황 | Approach |
|
|
|---|---|
|
|
| Long pause complaint (UI jank) | check Orinoco enabled (default), profile |
|
|
| Embedded V8 (custom flags) | enable concurrent + incremental marking |
|
|
| Constrained memory (IoT) | might disable concurrent (extra worker thread) |
|
|
| Benchmarking | report w/ default flags + GC trace |
|
|
|
|
**기본값**: 매 default flags (Orinoco on) — 매 manual disable 회피.
|
|
|
|
## 🔗 Graph
|
|
- 부모: [[Garbage_Collection]] · [[V8 엔진 힙 아키텍처|V8 Heap Architecture]]
|
|
- 변형: [[Incremental_Marking]] · [[Concurrent_Marking]] · [[Mark-Sweep]]
|
|
- 응용: [[Old_Space]] · [[Pointer_Compression]] · [[Write Barrier|Write_Barrier]]
|
|
- Adjacent: [[Generational_Hypothesis]] · [[Snapshots]] · [[Multi-threaded Architecture]]
|
|
|
|
## 🤖 LLM 활용
|
|
**언제**: V8 GC internals 학습, Node.js/Chrome perf 분석, GC pause 회귀 추적.
|
|
**언제 X**: non-V8 runtime (Hermes는 별도 GC), Java/Go GC (G1/ZGC/Shenandoah는 다른 design).
|
|
|
|
## ❌ 안티패턴
|
|
- **Disabling concurrent marking blindly**: 매 measurement 없이 — 보통 perf 악화.
|
|
- **Huge mutation in hot loop**: 매 write barrier overload.
|
|
- **Forcing `global.gc()` 빈번**: 매 production 절대 X — Orinoco가 알아서 함.
|
|
- **Confusing minor (scavenge) and major (mark-sweep)**: 매 trace 해석 오류.
|
|
|
|
## 🧪 검증 / 중복
|
|
- Verified (V8 blog "Orinoco" series 2016-2019, V8 source `src/heap/`, Mathias Bynens & Benedikt Meurer talks 2017-2020).
|
|
- 신뢰도 A.
|
|
|
|
## 🕓 Changelog
|
|
| 날짜 | 변경 |
|
|
|---|---|
|
|
| 2026-05-08 | Phase 1 |
|
|
| 2026-05-10 | Manual cleanup — Orinoco GC project (concurrent/parallel/incremental) |
|