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Phase 54-60: Memory-Lean mode, Balanced mode stabilization, M1 (50%) achievement ## Summary Completed Phase 54-60 optimization work: **Phase 54-56: Memory-Lean mode (LEAN+OFF prewarm suppression)** - Implemented ss_mem_lean_env_box.h with ENV gates - Balanced mode (LEAN+OFF) promoted as production default - Result: +1.2% throughput, better stability, zero syscall overhead - Added to bench_profile.h: MIXED_TINYV3_C7_BALANCED preset **Phase 57: 60-min soak finalization** - Balanced mode: 60-min soak, RSS drift 0%, CV 5.38% - Speed-first mode: 60-min soak, RSS drift 0%, CV 1.58% - Syscall budget: 1.25e-7/op (800× under target) - Status: PRODUCTION-READY **Phase 59: 50% recovery baseline rebase** - hakmem FAST (Balanced): 59.184M ops/s, CV 1.31% - mimalloc: 120.466M ops/s, CV 3.50% - Ratio: 49.13% (M1 ACHIEVED within statistical noise) - Superior stability: 2.68× better CV than mimalloc **Phase 60: Alloc pass-down SSOT (NO-GO)** - Implemented alloc_passdown_ssot_env_box.h - Modified malloc_tiny_fast.h for SSOT pattern - Result: -0.46% (NO-GO) - Key lesson: SSOT not applicable where early-exit already optimized ## Key Metrics - Performance: 49.13% of mimalloc (M1 effectively achieved) - Stability: CV 1.31% (superior to mimalloc 3.50%) - Syscall budget: 1.25e-7/op (excellent) - RSS: 33MB stable, 0% drift over 60 minutes ## Files Added/Modified New boxes: - core/box/ss_mem_lean_env_box.h - core/box/ss_release_policy_box.{h,c} - core/box/alloc_passdown_ssot_env_box.h Scripts: - scripts/soak_mixed_single_process.sh - scripts/analyze_epoch_tail_csv.py - scripts/soak_mixed_rss.sh - scripts/calculate_percentiles.py - scripts/analyze_soak.py Documentation: Phase 40-60 analysis documents ## Design Decisions 1. Profile separation (core/bench_profile.h): - MIXED_TINYV3_C7_SAFE: Speed-first (no LEAN) - MIXED_TINYV3_C7_BALANCED: Balanced mode (LEAN+OFF) 2. Box Theory compliance: - All ENV gates reversible (HAKMEM_SS_MEM_LEAN, HAKMEM_ALLOC_PASSDOWN_SSOT) - Single conversion points maintained - No physical deletions (compile-out only) 3. Lessons learned: - SSOT effective only where redundancy exists (Phase 60 showed limits) - Branch prediction extremely effective (~0 cycles for well-predicted branches) - Early-exit pattern valuable even when seemingly redundant 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
2025-12-17 06:24:01 +09:00
# Phase 48: Rebasemimalloc/system/jemalloc+ Stability Suite
目的: Phase 39 以降で **FAST baseline が大きく動いた**ため、`docs/analysis/PERFORMANCE_TARGETS_SCORECARD.md` の参照値mimalloc/system/jemalloc/libcを **同一条件で再計測**して更新する。あわせて「速さ以外の勝ち筋」syscall/RSS/長時間安定性)の **測定ルーチン**を固定する。
方針Box Theory:
- **測定は clean env** を正とする: `scripts/run_mixed_10_cleanenv.sh`
- **比較は FAST build を正**Standard/OBSERVE は別目的)
- **link-out / 物理削除はしない**layout tax で符号反転するため。compile-out で運用する。
---
## Step 0: 準備(ビルド)
```bash
make bench_random_mixed_hakmem_minimal
make bench_random_mixed_system
make bench_random_mixed_mi
```
任意jemalloc がある場合のみ:
```bash
ls -la /lib/x86_64-linux-gnu/libjemalloc.so.2
```
---
## Step 1: Mixed 10-run rebase同一スクリプトで回す
### 1-A) hakmem FAST
```bash
BENCH_BIN=./bench_random_mixed_hakmem_minimal scripts/run_mixed_10_cleanenv.sh
```
### 1-B) system malloc別バイナリ reference
```bash
BENCH_BIN=./bench_random_mixed_system scripts/run_mixed_10_cleanenv.sh
```
### 1-C) mimalloc別バイナリ reference
```bash
BENCH_BIN=./bench_random_mixed_mi scripts/run_mixed_10_cleanenv.sh
```
### 1-D) jemallocLD_PRELOAD reference、任意
```bash
LD_PRELOAD=/lib/x86_64-linux-gnu/libjemalloc.so.2 \
BENCH_BIN=./bench_random_mixed_system scripts/run_mixed_10_cleanenv.sh
```
更新先SSOT:
- `docs/analysis/PERFORMANCE_TARGETS_SCORECARD.md``Current snapshot``Reference allocators`
---
## Step 2: Syscall budgetsteady-state OS churn
目的: warmup 後に `mmap/munmap/madvise` が暴れていないことを確認するmimallocに対する勝ち筋の1つ
内部カウンタ(推奨、短時間):
```bash
HAKMEM_SS_OS_STATS=1 BENCH_BIN=./bench_random_mixed_hakmem_minimal \
ITERS=200000000 WS=400 RUNS=1 scripts/run_mixed_10_cleanenv.sh
```
チェック:
- `[SS_OS_STATS] ... mmap_total=... madvise=... madvise_disabled=...`
- 目標: warmup 後に **増え続けない** / “極端に多くない”
---
## Step 3: RSS/長時間安定性soak
目的: 「速さ以外の勝ち筋」を数値化するRSS drift / ops/s drift / CV
推奨3060分、FAST build:
- RSS drift: **+5% 以内**(目安)
- ops/s drift: **-5% 以上落ちない**
- CV: **~12%** を維持
実施方法:
- まずは `docs/analysis/PERFORMANCE_TARGETS_SCORECARD.md``Memory stability / Long-run stability` を SSOT とし、測定テンプレを追記するスクリプト化は別PhaseでOK
---
## 判定
- Phase 48 は「最適化」ではなく「**基準の固定**」が目的。
- GO/NO-GO は無し(測定結果をスコアカードへ反映して完了)。