test_perf_phase3.py
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| 1 | """Phase 3 — Performance regression tests. |
| 2 | |
| 3 | Target metrics (measured on a 2024 MacBook Pro M4, macOS 15): |
| 4 | |
| 5 | Phase 3.1 — Linux-kernel commit throughput |
| 6 | write_commit: ≥ 1 000 commits/sec |
| 7 | write_object: ≥ 2 000 objects/sec |
| 8 | build_snapshot_manifest: ≥ 10 000 files/sec |
| 9 | muse commit (e2e, 1 000-file workdir): < 5 000 ms |
| 10 | |
| 11 | Phase 3.2 — Concurrent agent write storm |
| 12 | 200 threads × write_object: all objects readable, no corruption |
| 13 | 200 threads × write_commit: all commits readable, no corruption |
| 14 | 100 threads × write_head_commit: last-write-wins, valid ID written |
| 15 | |
| 16 | Phase 3.3 — Memory ceiling |
| 17 | write_commit (10 000 commits): peak RSS < 512 MiB |
| 18 | build_snapshot_manifest (5 000 files): peak RSS < 128 MiB |
| 19 | |
| 20 | Phase 3.3 extended — Linux-scale memory ceiling (100k / 75k) |
| 21 | get_all_commits (100 000 commits): peak RSS < 2 GiB [@slow] |
| 22 | get_commits_for_branch walk-cap: max_walk_commits bounds RSS |
| 23 | muse log --json pseudo-streaming: no double-buffer |
| 24 | build_snapshot_manifest (75 000 files): peak RSS < 512 MiB [@slow] |
| 25 | find_merge_base (deep chain): cap fires, no OOM |
| 26 | walk_commits_between: silent truncation at cap, not OOM |
| 27 | |
| 28 | All slow tests are decorated with ``@pytest.mark.slow`` and are skipped by |
| 29 | default. Run the full suite with ``pytest tests/test_perf_phase3.py -v``. |
| 30 | """ |
| 31 | |
| 32 | from __future__ import annotations |
| 33 | |
| 34 | type _FileStore = dict[str, bytes] |
| 35 | |
| 36 | import datetime |
| 37 | import os |
| 38 | import pathlib |
| 39 | import resource |
| 40 | import sys |
| 41 | import threading |
| 42 | import time |
| 43 | import tracemalloc |
| 44 | |
| 45 | import pytest |
| 46 | from unittest.mock import patch |
| 47 | |
| 48 | from muse.core.object_store import ( |
| 49 | _created_object_shards, |
| 50 | has_object, |
| 51 | object_path, |
| 52 | read_object, |
| 53 | write_object, |
| 54 | ) |
| 55 | from muse.core.merge_engine import find_merge_base |
| 56 | from muse.core.snapshot import build_snapshot_manifest |
| 57 | from muse.core.ids import hash_commit as compute_commit_id |
| 58 | from muse.core.refs import ( |
| 59 | write_branch_ref, |
| 60 | write_head_commit, |
| 61 | ) |
| 62 | from muse.core.commits import ( |
| 63 | CommitRecord, |
| 64 | get_all_commits, |
| 65 | get_commits_for_branch, |
| 66 | read_commit, |
| 67 | walk_commits_between_result, |
| 68 | write_commit, |
| 69 | ) |
| 70 | |
| 71 | # --------------------------------------------------------------------------- |
| 72 | # Helpers |
| 73 | # --------------------------------------------------------------------------- |
| 74 | |
| 75 | |
| 76 | from muse.core.types import blob_id, fake_id, split_id |
| 77 | from muse.core.paths import config_toml_path, heads_dir, muse_dir, repo_json_path |
| 78 | |
| 79 | |
| 80 | |
| 81 | def _repo(tmp_path: pathlib.Path) -> pathlib.Path: |
| 82 | dot_muse = muse_dir(tmp_path) |
| 83 | dot_muse.mkdir() |
| 84 | (dot_muse / "repo.json").write_text('{"repo_id": "bench", "owner": "bench"}') |
| 85 | (dot_muse / "commits").mkdir() |
| 86 | (dot_muse / "snapshots").mkdir() |
| 87 | (dot_muse / "refs" / "heads").mkdir(parents=True) |
| 88 | (dot_muse / "HEAD").write_text("ref: refs/heads/main\n") |
| 89 | return tmp_path |
| 90 | |
| 91 | |
| 92 | def _write_chain( |
| 93 | repo: pathlib.Path, |
| 94 | branch: str, |
| 95 | n: int, |
| 96 | snap_id: str = fake_id("chain-snap"), |
| 97 | start: int = 0, |
| 98 | ) -> str: |
| 99 | """Write a linear commit chain of length *n* and return the tip commit ID. |
| 100 | |
| 101 | Sets the branch ref to the tip so ``get_commits_for_branch`` can walk it. |
| 102 | """ |
| 103 | parent: str | None = None |
| 104 | tip = "" |
| 105 | for i in range(start, start + n): |
| 106 | msg = f"chain-{i:07d}" |
| 107 | ts = datetime.datetime(2026, 1, 1, i % 3600 // 3600, i % 3600 % 60, tzinfo=datetime.timezone.utc) |
| 108 | cid = compute_commit_id( |
| 109 | parent_ids=[parent] if parent else [], |
| 110 | snapshot_id=snap_id, |
| 111 | message=msg, |
| 112 | committed_at_iso=ts.isoformat(), |
| 113 | author="chain-agent",) |
| 114 | rec = CommitRecord( |
| 115 | commit_id=cid, |
| 116 | branch=branch, |
| 117 | snapshot_id=snap_id, |
| 118 | message=msg, |
| 119 | committed_at=ts, |
| 120 | parent_commit_id=parent, |
| 121 | parent2_commit_id=None, |
| 122 | author="chain-agent", |
| 123 | metadata={}, |
| 124 | structured_delta=None, |
| 125 | sem_ver_bump="none", |
| 126 | breaking_changes=[], |
| 127 | agent_id="", |
| 128 | model_id="", |
| 129 | toolchain_id="", |
| 130 | prompt_hash="", |
| 131 | signature="", |
| 132 | signer_key_id="", |
| 133 | ) |
| 134 | write_commit(repo, rec) |
| 135 | parent = cid |
| 136 | tip = cid |
| 137 | write_branch_ref(repo, branch, tip) |
| 138 | return tip |
| 139 | |
| 140 | |
| 141 | def _make_commit(index: int, snap_id: str, parent: str | None = None) -> CommitRecord: |
| 142 | """Build a CommitRecord whose ``commit_id`` passes content-hash verification.""" |
| 143 | ts = datetime.datetime(2026, 1, 1, tzinfo=datetime.timezone.utc) |
| 144 | msg = f"commit-{index:07d}" |
| 145 | cid = compute_commit_id( |
| 146 | parent_ids=[parent] if parent else [], |
| 147 | snapshot_id=snap_id, |
| 148 | message=msg, |
| 149 | committed_at_iso=ts.isoformat(), |
| 150 | author="perf-agent",) |
| 151 | return CommitRecord( |
| 152 | commit_id=cid, |
| 153 | branch="main", |
| 154 | snapshot_id=snap_id, |
| 155 | message=msg, |
| 156 | committed_at=ts, |
| 157 | parent_commit_id=parent, |
| 158 | parent2_commit_id=None, |
| 159 | author="perf-agent", |
| 160 | metadata={}, |
| 161 | structured_delta=None, |
| 162 | sem_ver_bump="none", |
| 163 | breaking_changes=[], |
| 164 | agent_id="", |
| 165 | model_id="", |
| 166 | toolchain_id="", |
| 167 | prompt_hash="", |
| 168 | signature="", |
| 169 | signer_key_id="", |
| 170 | ) |
| 171 | |
| 172 | |
| 173 | # --------------------------------------------------------------------------- |
| 174 | # Phase 3.1 — Linux-kernel commit throughput |
| 175 | # --------------------------------------------------------------------------- |
| 176 | |
| 177 | |
| 178 | class TestWriteCommitThroughput: |
| 179 | """write_commit must sustain ≥ 1 000 commits/sec in isolation. |
| 180 | |
| 181 | The Linux-kernel migration target is 472 commits/sec over 850 000 commits |
| 182 | (< 30 min). A 1 000 commits/sec floor gives comfortable headroom for |
| 183 | real workload overhead (snapshot building, object writes, disk pressure). |
| 184 | |
| 185 | fsync is mocked: these tests measure msgpack serialisation + filesystem |
| 186 | metadata throughput, not OS I/O durability. Durability ordering is |
| 187 | verified by test_integrity_I2_fsync.py. |
| 188 | """ |
| 189 | |
| 190 | _MIN_COMMITS_PER_SEC = 1_000 |
| 191 | |
| 192 | @pytest.fixture(autouse=True) |
| 193 | def no_fsync(self) -> None: |
| 194 | """Mock out all fsync calls so the test measures algorithmic throughput.""" |
| 195 | with patch("muse.core.commits.os.fsync", return_value=None): |
| 196 | yield |
| 197 | |
| 198 | @pytest.mark.slow |
| 199 | def test_write_commit_throughput_10k(self, tmp_path: pathlib.Path) -> None: |
| 200 | """Write 10 000 commits and assert throughput ≥ 1 000 commits/sec.""" |
| 201 | repo = _repo(tmp_path) |
| 202 | snap_id = fake_id("snap-a") |
| 203 | N = 10_000 |
| 204 | commits = [_make_commit(i, snap_id) for i in range(N)] |
| 205 | |
| 206 | t0 = time.perf_counter() |
| 207 | for rec in commits: |
| 208 | write_commit(repo, rec) |
| 209 | elapsed = time.perf_counter() - t0 |
| 210 | rate = N / elapsed |
| 211 | |
| 212 | assert rate >= self._MIN_COMMITS_PER_SEC, ( |
| 213 | f"write_commit throughput {rate:.0f} commits/sec is below the " |
| 214 | f"minimum {self._MIN_COMMITS_PER_SEC} commits/sec. " |
| 215 | f"(10k commits took {elapsed:.2f}s. " |
| 216 | f"Linux-kernel migration target: 472 commits/sec.)" |
| 217 | ) |
| 218 | |
| 219 | def test_write_commit_throughput_1k_fast(self, tmp_path: pathlib.Path) -> None: |
| 220 | """Smoke-speed: 1 000 commits must complete within 5 seconds.""" |
| 221 | repo = _repo(tmp_path) |
| 222 | snap_id = fake_id("snap-b") |
| 223 | N = 1_000 |
| 224 | commits = [_make_commit(i, snap_id) for i in range(N)] |
| 225 | |
| 226 | t0 = time.perf_counter() |
| 227 | for rec in commits: |
| 228 | write_commit(repo, rec) |
| 229 | elapsed = time.perf_counter() - t0 |
| 230 | |
| 231 | assert elapsed <= 15.0, ( |
| 232 | f"1 000 write_commit calls took {elapsed:.2f}s — expected ≤ 15.0s." |
| 233 | ) |
| 234 | |
| 235 | |
| 236 | class TestWriteObjectThroughput: |
| 237 | """write_object must sustain ≥ 1 500 objects/sec in isolation. |
| 238 | |
| 239 | fsync is mocked: the test measures mkstemp + hash-verify + fchmod + |
| 240 | os.replace throughput without OS I/O latency. Durability ordering is |
| 241 | verified by test_integrity_I2_fsync.py. |
| 242 | """ |
| 243 | |
| 244 | _MIN_OBJECTS_PER_SEC = 1_500 |
| 245 | |
| 246 | @pytest.fixture(autouse=True) |
| 247 | def no_fsync(self) -> None: |
| 248 | """Mock out all fsync calls so the test measures algorithmic throughput.""" |
| 249 | with patch("muse.core.object_store._fsync_fd", return_value=None): |
| 250 | yield |
| 251 | |
| 252 | @pytest.mark.slow |
| 253 | def test_write_object_throughput_10k(self, tmp_path: pathlib.Path) -> None: |
| 254 | """Write 10 000 4-KiB objects and assert throughput ≥ 2 000 objects/sec.""" |
| 255 | repo = _repo(tmp_path) |
| 256 | N = 10_000 |
| 257 | items = [ |
| 258 | ( |
| 259 | blob_id(f"perf-obj-{i:08d}".encode() * 16), |
| 260 | f"perf-obj-{i:08d}".encode() * 16, |
| 261 | ) |
| 262 | for i in range(N) |
| 263 | ] |
| 264 | |
| 265 | t0 = time.perf_counter() |
| 266 | for oid, content in items: |
| 267 | write_object(repo, oid, content) |
| 268 | elapsed = time.perf_counter() - t0 |
| 269 | rate = N / elapsed |
| 270 | |
| 271 | assert rate >= self._MIN_OBJECTS_PER_SEC, ( |
| 272 | f"write_object throughput {rate:.0f} objects/sec is below the " |
| 273 | f"minimum {self._MIN_OBJECTS_PER_SEC} objects/sec. " |
| 274 | f"(10k objects took {elapsed:.2f}s.)" |
| 275 | ) |
| 276 | |
| 277 | @pytest.mark.perf |
| 278 | def test_write_object_throughput_1k_fast(self, tmp_path: pathlib.Path) -> None: |
| 279 | """Smoke-speed: 1 000 objects must complete within 2 seconds.""" |
| 280 | repo = _repo(tmp_path) |
| 281 | N = 1_000 |
| 282 | items = [ |
| 283 | ( |
| 284 | blob_id(f"fast-obj-{i:08d}".encode() * 8), |
| 285 | f"fast-obj-{i:08d}".encode() * 8, |
| 286 | ) |
| 287 | for i in range(N) |
| 288 | ] |
| 289 | |
| 290 | t0 = time.perf_counter() |
| 291 | for oid, content in items: |
| 292 | write_object(repo, oid, content) |
| 293 | elapsed = time.perf_counter() - t0 |
| 294 | |
| 295 | assert elapsed <= 6.0, ( |
| 296 | f"1 000 write_object calls took {elapsed:.2f}s — expected ≤ 6.0s." |
| 297 | ) |
| 298 | |
| 299 | |
| 300 | class TestSnapshotManifestThroughput: |
| 301 | """build_snapshot_manifest must sustain ≥ 10 000 files/sec.""" |
| 302 | |
| 303 | _MIN_FILES_PER_SEC = 10_000 |
| 304 | |
| 305 | @pytest.mark.slow |
| 306 | def test_snapshot_5k_files(self, tmp_path: pathlib.Path) -> None: |
| 307 | """Build manifest of 5 000 files; assert ≥ 10 000 files/sec.""" |
| 308 | root = tmp_path / "workdir" |
| 309 | root.mkdir() |
| 310 | muse_dir(root).mkdir() |
| 311 | (repo_json_path(root)).write_text('{"repo_id": "bench"}') |
| 312 | |
| 313 | # 50 dirs × 100 files = 5 000 files |
| 314 | for d in range(50): |
| 315 | dp = root / f"pkg_{d:03d}" |
| 316 | dp.mkdir() |
| 317 | for f in range(100): |
| 318 | (dp / f"file_{f:03d}.py").write_bytes( |
| 319 | f"# content-{d}-{f}\n".encode() * 50 |
| 320 | ) |
| 321 | |
| 322 | t0 = time.perf_counter() |
| 323 | manifest = build_snapshot_manifest(root) |
| 324 | elapsed = time.perf_counter() - t0 |
| 325 | rate = len(manifest) / elapsed |
| 326 | |
| 327 | assert len(manifest) == 5_000 |
| 328 | assert rate >= self._MIN_FILES_PER_SEC, ( |
| 329 | f"build_snapshot_manifest throughput {rate:.0f} files/sec is below " |
| 330 | f"the minimum {self._MIN_FILES_PER_SEC} files/sec. " |
| 331 | f"(5k files took {elapsed:.3f}s.)" |
| 332 | ) |
| 333 | |
| 334 | def test_snapshot_500_files_fast(self, tmp_path: pathlib.Path) -> None: |
| 335 | """Smoke-speed: 500-file manifest must complete within 500 ms.""" |
| 336 | root = tmp_path / "workdir" |
| 337 | root.mkdir() |
| 338 | muse_dir(root).mkdir() |
| 339 | (repo_json_path(root)).write_text('{"repo_id": "bench"}') |
| 340 | |
| 341 | for d in range(25): |
| 342 | dp = root / f"pkg_{d:02d}" |
| 343 | dp.mkdir() |
| 344 | for f in range(20): |
| 345 | (dp / f"file_{f:02d}.py").write_bytes(b"x" * 200) |
| 346 | |
| 347 | t0 = time.perf_counter() |
| 348 | manifest = build_snapshot_manifest(root) |
| 349 | elapsed = time.perf_counter() - t0 |
| 350 | |
| 351 | assert len(manifest) == 500 |
| 352 | assert elapsed <= 0.5, ( |
| 353 | f"500-file manifest took {elapsed*1000:.1f} ms — expected ≤ 500 ms." |
| 354 | ) |
| 355 | |
| 356 | |
| 357 | # --------------------------------------------------------------------------- |
| 358 | # Phase 3.2 — Concurrent agent write storm |
| 359 | # --------------------------------------------------------------------------- |
| 360 | |
| 361 | |
| 362 | class TestConcurrentWriteObjectStorm: |
| 363 | """200 threads writing distinct objects — no corruption, no data loss.""" |
| 364 | |
| 365 | def test_200_threads_write_distinct_objects(self, tmp_path: pathlib.Path) -> None: |
| 366 | """200 threads each write 50 distinct objects; all must be readable after join.""" |
| 367 | repo = _repo(tmp_path) |
| 368 | N_THREADS = 200 |
| 369 | N_PER_THREAD = 50 |
| 370 | written: _FileStore = {} |
| 371 | lock = threading.Lock() |
| 372 | errors: list[str] = [] |
| 373 | |
| 374 | # Pre-compute all objects to avoid per-thread hashing noise. |
| 375 | all_items: list[list[tuple[str, bytes]]] = [] |
| 376 | for t in range(N_THREADS): |
| 377 | thread_items: list[tuple[str, bytes]] = [] |
| 378 | for i in range(N_PER_THREAD): |
| 379 | content = f"thread-{t:03d}-obj-{i:03d}".encode() * 4 |
| 380 | oid = blob_id(content) |
| 381 | thread_items.append((oid, content)) |
| 382 | with lock: |
| 383 | written[oid] = content |
| 384 | all_items.append(thread_items) |
| 385 | |
| 386 | def writer(items: list[tuple[str, bytes]]) -> None: |
| 387 | try: |
| 388 | for oid, content in items: |
| 389 | write_object(repo, oid, content) |
| 390 | except Exception as exc: |
| 391 | with lock: |
| 392 | errors.append(str(exc)) |
| 393 | |
| 394 | threads = [ |
| 395 | threading.Thread(target=writer, args=(all_items[t],)) |
| 396 | for t in range(N_THREADS) |
| 397 | ] |
| 398 | for th in threads: |
| 399 | th.start() |
| 400 | for th in threads: |
| 401 | th.join(timeout=30.0) |
| 402 | |
| 403 | assert not errors, f"Write errors during concurrent storm: {errors[:3]}" |
| 404 | |
| 405 | # Verify every object is readable and byte-identical. |
| 406 | missing: list[str] = [] |
| 407 | corrupt: list[str] = [] |
| 408 | for oid, expected in written.items(): |
| 409 | if not has_object(repo, oid): |
| 410 | missing.append(oid[:8]) |
| 411 | else: |
| 412 | actual = read_object(repo, oid) |
| 413 | if actual != expected: |
| 414 | corrupt.append(oid[:8]) |
| 415 | |
| 416 | assert not missing, f"{len(missing)} objects missing after concurrent write storm" |
| 417 | assert not corrupt, f"{len(corrupt)} objects corrupted after concurrent write storm" |
| 418 | |
| 419 | |
| 420 | class TestConcurrentWriteCommitStorm: |
| 421 | """200 threads writing distinct commits — all must be readable after join.""" |
| 422 | |
| 423 | def test_200_threads_write_distinct_commits(self, tmp_path: pathlib.Path) -> None: |
| 424 | """200 threads each write 25 distinct commits; all must be readable.""" |
| 425 | repo = _repo(tmp_path) |
| 426 | N_THREADS = 200 |
| 427 | N_PER_THREAD = 25 |
| 428 | snap_id = fake_id("snap-c") |
| 429 | all_records: list[list[CommitRecord]] = [] |
| 430 | errors: list[str] = [] |
| 431 | lock = threading.Lock() |
| 432 | |
| 433 | for t in range(N_THREADS): |
| 434 | thread_recs: list[CommitRecord] = [] |
| 435 | for i in range(N_PER_THREAD): |
| 436 | rec = _make_commit(t * N_PER_THREAD + i, snap_id) |
| 437 | thread_recs.append(rec) |
| 438 | all_records.append(thread_recs) |
| 439 | |
| 440 | def writer(recs: list[CommitRecord]) -> None: |
| 441 | try: |
| 442 | for rec in recs: |
| 443 | write_commit(repo, rec) |
| 444 | except Exception as exc: |
| 445 | with lock: |
| 446 | errors.append(str(exc)) |
| 447 | |
| 448 | threads = [ |
| 449 | threading.Thread(target=writer, args=(all_records[t],)) |
| 450 | for t in range(N_THREADS) |
| 451 | ] |
| 452 | for th in threads: |
| 453 | th.start() |
| 454 | for th in threads: |
| 455 | th.join(timeout=30.0) |
| 456 | |
| 457 | assert not errors, f"Write errors during concurrent commit storm: {errors[:3]}" |
| 458 | |
| 459 | # All commits must be readable. |
| 460 | total = N_THREADS * N_PER_THREAD |
| 461 | missing: list[str] = [] |
| 462 | for recs in all_records: |
| 463 | for rec in recs: |
| 464 | result = read_commit(repo, rec.commit_id) |
| 465 | if result is None: |
| 466 | missing.append(rec.commit_id[:8]) |
| 467 | |
| 468 | assert not missing, ( |
| 469 | f"{len(missing)}/{total} commits missing after concurrent write storm" |
| 470 | ) |
| 471 | |
| 472 | |
| 473 | class TestConcurrentWriteBranchRef: |
| 474 | """100 threads racing on write_branch_ref — last write wins, no corruption.""" |
| 475 | |
| 476 | def test_100_threads_write_branch_ref_last_write_wins( |
| 477 | self, tmp_path: pathlib.Path |
| 478 | ) -> None: |
| 479 | """100 threads each writing write_branch_ref; result must be a valid 64-char hex ID.""" |
| 480 | repo = _repo(tmp_path) |
| 481 | refs_dir = heads_dir(repo) # already created by _repo() |
| 482 | |
| 483 | N = 100 |
| 484 | snap_id = fake_id("snap-d") |
| 485 | commit_ids: list[str] = [] |
| 486 | errors: list[str] = [] |
| 487 | lock = threading.Lock() |
| 488 | |
| 489 | for i in range(N): |
| 490 | cid = compute_commit_id(parent_ids=[], snapshot_id=snap_id, message=f"head-{i}", committed_at_iso="2026-01-01T00:00:00+00:00") |
| 491 | commit_ids.append(cid) |
| 492 | |
| 493 | def writer(cid: str) -> None: |
| 494 | try: |
| 495 | write_branch_ref(repo, "main", cid) |
| 496 | except Exception as exc: |
| 497 | with lock: |
| 498 | errors.append(str(exc)) |
| 499 | |
| 500 | threads = [threading.Thread(target=writer, args=(commit_ids[i],)) for i in range(N)] |
| 501 | for th in threads: |
| 502 | th.start() |
| 503 | for th in threads: |
| 504 | th.join(timeout=10.0) |
| 505 | |
| 506 | assert not errors, f"Errors during concurrent write_branch_ref: {errors[:3]}" |
| 507 | |
| 508 | # The branch ref must contain exactly one of the written IDs. |
| 509 | ref_file = refs_dir / "main" |
| 510 | assert ref_file.exists(), "Branch ref file was lost after concurrent writes" |
| 511 | final_cid = ref_file.read_text(encoding="utf-8").strip() |
| 512 | # Commit IDs are now "sha256:<64hex>" = 71 chars |
| 513 | assert final_cid.startswith("sha256:"), f"Branch ref has unexpected format: {final_cid!r}" |
| 514 | _, hex_part = split_id(final_cid) |
| 515 | assert len(hex_part) == 64, f"Branch ref hex part has unexpected length: {final_cid!r}" |
| 516 | assert all(c in "0123456789abcdef" for c in hex_part), ( |
| 517 | f"Branch ref is not a valid hex ID: {final_cid!r}" |
| 518 | ) |
| 519 | assert final_cid in commit_ids, ( |
| 520 | f"Branch ref {final_cid[:19]} is not one of the written IDs" |
| 521 | ) |
| 522 | |
| 523 | |
| 524 | # --------------------------------------------------------------------------- |
| 525 | # Phase 3.3 — Memory ceiling under load |
| 526 | # --------------------------------------------------------------------------- |
| 527 | |
| 528 | |
| 529 | class TestMemoryCeiling: |
| 530 | """Peak memory must not grow proportionally to the number of objects or commits.""" |
| 531 | |
| 532 | _MAX_WRITE_COMMIT_MIB = 512 |
| 533 | _MAX_SNAPSHOT_MIB = 128 |
| 534 | |
| 535 | @pytest.mark.slow |
| 536 | def test_write_10k_commits_peak_rss_under_512_mib( |
| 537 | self, tmp_path: pathlib.Path |
| 538 | ) -> None: |
| 539 | """Writing 10 000 commits must not exceed 512 MiB peak RSS. |
| 540 | |
| 541 | write_commit buffers one commit at a time; it must not accumulate |
| 542 | a list of all commits in memory. |
| 543 | """ |
| 544 | repo = _repo(tmp_path) |
| 545 | snap_id = fake_id("snap-e") |
| 546 | N = 10_000 |
| 547 | |
| 548 | tracemalloc.start() |
| 549 | tracemalloc.clear_traces() |
| 550 | |
| 551 | for i in range(N): |
| 552 | rec = _make_commit(i, snap_id) |
| 553 | write_commit(repo, rec) |
| 554 | |
| 555 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 556 | tracemalloc.stop() |
| 557 | |
| 558 | peak_mib = peak_bytes / (1024 * 1024) |
| 559 | assert peak_mib <= self._MAX_WRITE_COMMIT_MIB, ( |
| 560 | f"write_commit peak allocation {peak_mib:.1f} MiB exceeds " |
| 561 | f"{self._MAX_WRITE_COMMIT_MIB} MiB for 10k commits. " |
| 562 | "write_commit must stream one record at a time." |
| 563 | ) |
| 564 | |
| 565 | def test_snapshot_5k_files_peak_rss_under_128_mib( |
| 566 | self, tmp_path: pathlib.Path |
| 567 | ) -> None: |
| 568 | """build_snapshot_manifest on 5 000 small files stays under 128 MiB.""" |
| 569 | root = tmp_path / "workdir" |
| 570 | root.mkdir() |
| 571 | muse_dir(root).mkdir() |
| 572 | (repo_json_path(root)).write_text('{"repo_id": "bench"}') |
| 573 | |
| 574 | for d in range(50): |
| 575 | dp = root / f"d_{d:02d}" |
| 576 | dp.mkdir() |
| 577 | for f in range(100): |
| 578 | (dp / f"f_{f:02d}.txt").write_bytes(b"x" * 512) |
| 579 | |
| 580 | tracemalloc.start() |
| 581 | tracemalloc.clear_traces() |
| 582 | build_snapshot_manifest(root) |
| 583 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 584 | tracemalloc.stop() |
| 585 | |
| 586 | peak_mib = peak_bytes / (1024 * 1024) |
| 587 | assert peak_mib <= self._MAX_SNAPSHOT_MIB, ( |
| 588 | f"build_snapshot_manifest peak allocation {peak_mib:.1f} MiB " |
| 589 | f"exceeds {self._MAX_SNAPSHOT_MIB} MiB for 5k files. " |
| 590 | "The manifest dict must not accumulate large intermediate buffers." |
| 591 | ) |
| 592 | |
| 593 | |
| 594 | # --------------------------------------------------------------------------- |
| 595 | # Phase 3.1 — Shard-cache amortisation (regression guard) |
| 596 | # --------------------------------------------------------------------------- |
| 597 | |
| 598 | |
| 599 | class TestShardCacheAmortisation: |
| 600 | """The shard-validation cache eliminates O(objects) resolve() calls. |
| 601 | |
| 602 | This test is not a timing test — it verifies the structural invariant: |
| 603 | after N writes to the same shard, _created_object_shards contains exactly |
| 604 | that shard entry and subsequent writes to the same shard do not re-trigger |
| 605 | path-resolution (proved by exercising the idempotent write path). |
| 606 | """ |
| 607 | |
| 608 | def test_shard_cache_populated_after_first_write( |
| 609 | self, tmp_path: pathlib.Path |
| 610 | ) -> None: |
| 611 | """After the first write to a shard, _created_object_shards contains its path.""" |
| 612 | repo = _repo(tmp_path) |
| 613 | content = b"shard-cache-test" |
| 614 | oid = blob_id(content) |
| 615 | shard_str = str(object_path(repo, oid).parent) |
| 616 | |
| 617 | # Ensure cache starts without this shard. |
| 618 | _created_object_shards.discard(shard_str) |
| 619 | |
| 620 | write_object(repo, oid, content) |
| 621 | |
| 622 | assert shard_str in _created_object_shards, ( |
| 623 | f"Shard {oid[:2]} not recorded in _created_object_shards after first write. " |
| 624 | "The amortisation optimisation is not active." |
| 625 | ) |
| 626 | |
| 627 | def test_repeated_writes_to_same_shard_succeed( |
| 628 | self, tmp_path: pathlib.Path |
| 629 | ) -> None: |
| 630 | """50 distinct writes to the same shard all land correctly.""" |
| 631 | repo = _repo(tmp_path) |
| 632 | # Force a fixed shard prefix by constructing objects with the same prefix. |
| 633 | # We use a known prefix and craft content that happens to hash to it. |
| 634 | # Easier: just write 50 objects and verify they all land. |
| 635 | N = 50 |
| 636 | items = [ |
| 637 | ( |
| 638 | blob_id(f"repeat-shard-{i:04d}".encode()), |
| 639 | f"repeat-shard-{i:04d}".encode(), |
| 640 | ) |
| 641 | for i in range(N) |
| 642 | ] |
| 643 | |
| 644 | for oid, content in items: |
| 645 | write_object(repo, oid, content) |
| 646 | |
| 647 | missing = [oid[:8] for oid, _ in items if not has_object(repo, oid)] |
| 648 | assert not missing, ( |
| 649 | f"{len(missing)} objects missing after repeated writes: {missing[:5]}" |
| 650 | ) |
| 651 | |
| 652 | def test_idempotent_write_bypasses_shard_write( |
| 653 | self, tmp_path: pathlib.Path |
| 654 | ) -> None: |
| 655 | """write_object returns False (idempotent) on the second call for the same OID.""" |
| 656 | repo = _repo(tmp_path) |
| 657 | content = b"idempotent-check" |
| 658 | oid = blob_id(content) |
| 659 | |
| 660 | first = write_object(repo, oid, content) |
| 661 | second = write_object(repo, oid, content) |
| 662 | |
| 663 | assert first is True, "First write should return True" |
| 664 | assert second is False, "Second write should return False (already exists)" |
| 665 | |
| 666 | |
| 667 | # --------------------------------------------------------------------------- |
| 668 | # Phase 3.3 extended — Linux-scale memory ceiling |
| 669 | # --------------------------------------------------------------------------- |
| 670 | |
| 671 | |
| 672 | class TestGetAllCommitsMemory: |
| 673 | """get_all_commits must not OOM under Linux-scale commit counts. |
| 674 | |
| 675 | This is the highest-risk accumulator: it loads *every* CommitRecord in the |
| 676 | store into a list simultaneously with no cap. At 100k commits × ~2 KB per |
| 677 | serialised record the baseline is ~200 MiB. Commits with large |
| 678 | ``structured_delta`` payloads can be 100 KB each (100k × 100 KB = 10 GiB). |
| 679 | The 64 MiB per-record msgpack cap (MAX_MSGPACK_BYTES) provides the guard. |
| 680 | |
| 681 | The @slow variants build real on-disk commit chains; the fast variant uses |
| 682 | a small chain to confirm the structural property with tracemalloc. |
| 683 | """ |
| 684 | |
| 685 | def test_get_all_commits_1k_peak_rss_under_128_mib( |
| 686 | self, tmp_path: pathlib.Path |
| 687 | ) -> None: |
| 688 | """get_all_commits on 1 000 commits stays under 128 MiB (fast smoke).""" |
| 689 | repo = _repo(tmp_path) |
| 690 | N = 1_000 |
| 691 | snap_id = fake_id("snap-aa") |
| 692 | for i in range(N): |
| 693 | write_commit(repo, _make_commit(i, snap_id)) |
| 694 | |
| 695 | tracemalloc.start() |
| 696 | tracemalloc.clear_traces() |
| 697 | results = get_all_commits(repo) |
| 698 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 699 | tracemalloc.stop() |
| 700 | |
| 701 | assert len(results) == N, f"Expected {N} commits, got {len(results)}" |
| 702 | peak_mib = peak_bytes / (1024 * 1024) |
| 703 | assert peak_mib <= 128, ( |
| 704 | f"get_all_commits({N}) peak {peak_mib:.1f} MiB — expected ≤ 128 MiB. " |
| 705 | "CommitRecord size has grown; re-audit the dataclass fields." |
| 706 | ) |
| 707 | |
| 708 | @pytest.mark.slow |
| 709 | def test_get_all_commits_100k_under_2_gib( |
| 710 | self, tmp_path: pathlib.Path |
| 711 | ) -> None: |
| 712 | """get_all_commits on 100 000 commits stays under 2 GiB. |
| 713 | |
| 714 | 100k × minimal CommitRecord ≈ 200 MiB. The 2 GiB ceiling allows a 10× |
| 715 | margin for realistic payloads (metadata, structured_delta) while still |
| 716 | catching runaway accumulation. |
| 717 | """ |
| 718 | repo = _repo(tmp_path) |
| 719 | N = 100_000 |
| 720 | snap_id = fake_id("snap-bb") |
| 721 | |
| 722 | for i in range(N): |
| 723 | write_commit(repo, _make_commit(i, snap_id)) |
| 724 | |
| 725 | _MAX_MIB = 2_048 # 2 GiB |
| 726 | |
| 727 | tracemalloc.start() |
| 728 | tracemalloc.clear_traces() |
| 729 | results = get_all_commits(repo) |
| 730 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 731 | tracemalloc.stop() |
| 732 | |
| 733 | assert len(results) == N |
| 734 | peak_mib = peak_bytes / (1024 * 1024) |
| 735 | assert peak_mib <= _MAX_MIB, ( |
| 736 | f"get_all_commits(100k) peak {peak_mib:.1f} MiB exceeds {_MAX_MIB} MiB. " |
| 737 | "The function loads all CommitRecords into a list simultaneously — " |
| 738 | "consider streaming or paginating for very large repos." |
| 739 | ) |
| 740 | |
| 741 | |
| 742 | class TestGetCommitsForBranchWalkCap: |
| 743 | """get_commits_for_branch must honour its walk cap. |
| 744 | |
| 745 | The cap is the primary memory guard for ``muse log --json``. A branch with |
| 746 | N commits deeper than the cap must return exactly cap records, not N — even |
| 747 | when filters are active and the caller passes max_count=0. |
| 748 | """ |
| 749 | |
| 750 | def test_walk_cap_bounds_returned_records( |
| 751 | self, tmp_path: pathlib.Path |
| 752 | ) -> None: |
| 753 | """Chain of 500 commits with cap=100 returns exactly 100 records.""" |
| 754 | repo = _repo(tmp_path) |
| 755 | N = 500 |
| 756 | CAP = 100 |
| 757 | _write_chain(repo, "main", N) |
| 758 | |
| 759 | results = get_commits_for_branch(repo, "main", max_count=CAP) |
| 760 | |
| 761 | assert len(results) == CAP, ( |
| 762 | f"Expected cap={CAP} records, got {len(results)} — " |
| 763 | "walk cap is not being respected." |
| 764 | ) |
| 765 | |
| 766 | def test_walk_cap_memory_bounded_deep_chain( |
| 767 | self, tmp_path: pathlib.Path |
| 768 | ) -> None: |
| 769 | """2 000-commit chain with default cap stays under 64 MiB.""" |
| 770 | repo = _repo(tmp_path) |
| 771 | N = 2_000 |
| 772 | CAP = 500 |
| 773 | _write_chain(repo, "main", N) |
| 774 | |
| 775 | tracemalloc.start() |
| 776 | tracemalloc.clear_traces() |
| 777 | results = get_commits_for_branch(repo, "main", max_count=CAP) |
| 778 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 779 | tracemalloc.stop() |
| 780 | |
| 781 | assert len(results) == CAP |
| 782 | peak_mib = peak_bytes / (1024 * 1024) |
| 783 | assert peak_mib <= 64, ( |
| 784 | f"get_commits_for_branch(cap={CAP}) peak {peak_mib:.1f} MiB — " |
| 785 | f"expected ≤ 64 MiB for {CAP} records." |
| 786 | ) |
| 787 | |
| 788 | |
| 789 | class TestLogJsonStreaming: |
| 790 | """``muse log --json`` must not double-buffer commit JSON strings. |
| 791 | |
| 792 | The previous implementation accumulated ``commit_jsons: list[str]`` before |
| 793 | writing to stdout — doubling peak memory vs. the CommitRecord list alone. |
| 794 | The fix uses a first-item flag to write each record inline immediately. |
| 795 | This test verifies the fix: tracemalloc peak for a 500-commit log should |
| 796 | not contain the signature of a large string buffer. |
| 797 | """ |
| 798 | |
| 799 | def test_log_json_output_is_valid_json( |
| 800 | self, tmp_path: pathlib.Path |
| 801 | ) -> None: |
| 802 | """muse log --json on a 100-commit branch emits valid JSON with all commits.""" |
| 803 | import json |
| 804 | |
| 805 | from tests.cli_test_helper import CliRunner |
| 806 | |
| 807 | repo = _repo(tmp_path) |
| 808 | N = 100 |
| 809 | _write_chain(repo, "main", N) |
| 810 | (config_toml_path(repo)).write_text("") |
| 811 | |
| 812 | runner = CliRunner() |
| 813 | result = runner.invoke( |
| 814 | None, |
| 815 | ["log", "--json", "--max-count", str(N)], |
| 816 | env={"MUSE_REPO_ROOT": str(repo)}, |
| 817 | ) |
| 818 | assert result.exit_code == 0, f"muse log --json failed:\n{result.output}" |
| 819 | |
| 820 | payload = json.loads(result.output) |
| 821 | assert "commits" in payload, f"Missing 'commits' key: {payload}" |
| 822 | assert len(payload["commits"]) == N, ( |
| 823 | f"Expected {N} commits in JSON output, got {len(payload['commits'])}" |
| 824 | ) |
| 825 | |
| 826 | def test_log_json_empty_repo_returns_empty_array( |
| 827 | self, tmp_path: pathlib.Path |
| 828 | ) -> None: |
| 829 | """muse log --json on a branch with no commits returns empty commits array.""" |
| 830 | import json |
| 831 | |
| 832 | from tests.cli_test_helper import CliRunner |
| 833 | |
| 834 | repo = _repo(tmp_path) |
| 835 | (config_toml_path(repo)).write_text("") |
| 836 | |
| 837 | runner = CliRunner() |
| 838 | result = runner.invoke( |
| 839 | None, |
| 840 | ["log", "--json"], |
| 841 | env={"MUSE_REPO_ROOT": str(repo)}, |
| 842 | ) |
| 843 | # No commits → either exit 0 with empty commits array or a graceful |
| 844 | # "(no commits)" message; both are acceptable. |
| 845 | if result.exit_code == 0 and result.output.startswith("{"): |
| 846 | payload = json.loads(result.output) |
| 847 | assert payload.get("commits") == [] |
| 848 | |
| 849 | |
| 850 | class TestFindMergeBaseMemory: |
| 851 | """find_merge_base must fire its cap cleanly, not OOM. |
| 852 | |
| 853 | The default ``max_ancestors`` cap is 50 000. A chain deeper than the cap |
| 854 | must raise ``MuseCLIError`` with an actionable message rather than |
| 855 | exhausting all available memory. This test confirms the error path, not |
| 856 | the OOM path. |
| 857 | """ |
| 858 | |
| 859 | def test_merge_base_cap_raises_gracefully_on_deep_chain( |
| 860 | self, tmp_path: pathlib.Path |
| 861 | ) -> None: |
| 862 | """Chain deeper than max_ancestors raises MuseCLIError, not MemoryError.""" |
| 863 | from muse.core.errors import MuseCLIError |
| 864 | |
| 865 | repo = _repo(tmp_path) |
| 866 | (config_toml_path(repo)).write_text( |
| 867 | "[limits]\nmax_ancestors = 50\n" |
| 868 | ) |
| 869 | |
| 870 | tip_a = _write_chain(repo, "branchA", 60, snap_id="cc" * 32) |
| 871 | # branchB is entirely separate — no common ancestor with branchA. |
| 872 | tip_b = _write_chain(repo, "branchB", 60, snap_id="dd" * 32, start=1000) |
| 873 | |
| 874 | with pytest.raises(MuseCLIError, match="max_ancestors"): |
| 875 | find_merge_base(repo, tip_a, tip_b) |
| 876 | |
| 877 | def test_merge_base_found_within_cap( |
| 878 | self, tmp_path: pathlib.Path |
| 879 | ) -> None: |
| 880 | """find_merge_base finds the base when both branches are within cap.""" |
| 881 | repo = _repo(tmp_path) |
| 882 | (config_toml_path(repo)).write_text( |
| 883 | "[limits]\nmax_ancestors = 500\n" |
| 884 | ) |
| 885 | |
| 886 | # Build a common root commit. |
| 887 | snap_id = "ee" * 32 |
| 888 | root_cid = compute_commit_id( |
| 889 | parent_ids=[], |
| 890 | snapshot_id=snap_id, |
| 891 | message="root", |
| 892 | committed_at_iso="2026-01-01T00:00:00+00:00", |
| 893 | author="test",) |
| 894 | root_rec = CommitRecord( |
| 895 | commit_id=root_cid, |
| 896 | branch="main", |
| 897 | snapshot_id=snap_id, |
| 898 | message="root", |
| 899 | committed_at=datetime.datetime(2026, 1, 1, tzinfo=datetime.timezone.utc), |
| 900 | parent_commit_id=None, |
| 901 | parent2_commit_id=None, |
| 902 | author="test", |
| 903 | metadata={}, |
| 904 | structured_delta=None, |
| 905 | sem_ver_bump="none", |
| 906 | breaking_changes=[], |
| 907 | agent_id="", |
| 908 | model_id="", |
| 909 | toolchain_id="", |
| 910 | prompt_hash="", |
| 911 | signature="", |
| 912 | signer_key_id="", |
| 913 | ) |
| 914 | write_commit(repo, root_rec) |
| 915 | |
| 916 | # Extend branchA and branchB from the same root. |
| 917 | parent_a: str | None = root_cid |
| 918 | tip_a = root_cid |
| 919 | for i in range(20): |
| 920 | msg = f"a-{i:04d}" |
| 921 | ts = datetime.datetime(2026, 1, 2, tzinfo=datetime.timezone.utc) |
| 922 | cid = compute_commit_id( |
| 923 | parent_ids=[parent_a] if parent_a else [], |
| 924 | snapshot_id=snap_id, |
| 925 | message=msg, |
| 926 | committed_at_iso=ts.isoformat(), |
| 927 | author="test",) |
| 928 | rec = CommitRecord( |
| 929 | commit_id=cid, |
| 930 | branch="branchA", |
| 931 | snapshot_id=snap_id, |
| 932 | message=msg, |
| 933 | committed_at=ts, |
| 934 | parent_commit_id=parent_a, |
| 935 | parent2_commit_id=None, |
| 936 | author="test", |
| 937 | metadata={}, |
| 938 | structured_delta=None, |
| 939 | sem_ver_bump="none", |
| 940 | breaking_changes=[], |
| 941 | agent_id="", |
| 942 | model_id="", |
| 943 | toolchain_id="", |
| 944 | prompt_hash="", |
| 945 | signature="", |
| 946 | signer_key_id="", |
| 947 | ) |
| 948 | write_commit(repo, rec) |
| 949 | parent_a = cid |
| 950 | tip_a = cid |
| 951 | |
| 952 | parent_b: str | None = root_cid |
| 953 | tip_b = root_cid |
| 954 | for i in range(15): |
| 955 | msg = f"b-{i:04d}" |
| 956 | ts = datetime.datetime(2026, 1, 3, tzinfo=datetime.timezone.utc) |
| 957 | cid = compute_commit_id( |
| 958 | parent_ids=[parent_b] if parent_b else [], |
| 959 | snapshot_id=snap_id, |
| 960 | message=msg, |
| 961 | committed_at_iso=ts.isoformat(), |
| 962 | author="test",) |
| 963 | rec = CommitRecord( |
| 964 | commit_id=cid, |
| 965 | branch="branchB", |
| 966 | snapshot_id=snap_id, |
| 967 | message=msg, |
| 968 | committed_at=ts, |
| 969 | parent_commit_id=parent_b, |
| 970 | parent2_commit_id=None, |
| 971 | author="test", |
| 972 | metadata={}, |
| 973 | structured_delta=None, |
| 974 | sem_ver_bump="none", |
| 975 | breaking_changes=[], |
| 976 | agent_id="", |
| 977 | model_id="", |
| 978 | toolchain_id="", |
| 979 | prompt_hash="", |
| 980 | signature="", |
| 981 | signer_key_id="", |
| 982 | ) |
| 983 | write_commit(repo, rec) |
| 984 | parent_b = cid |
| 985 | tip_b = cid |
| 986 | |
| 987 | base = find_merge_base(repo, tip_a, tip_b) |
| 988 | assert base == root_cid, ( |
| 989 | f"Expected merge base {root_cid[:8]}, got {base[:8] if base else None}" |
| 990 | ) |
| 991 | |
| 992 | def test_merge_base_memory_bounded_within_cap( |
| 993 | self, tmp_path: pathlib.Path |
| 994 | ) -> None: |
| 995 | """find_merge_base BFS uses bounded memory proportional to max_ancestors.""" |
| 996 | from muse.core.errors import MuseCLIError |
| 997 | |
| 998 | repo = _repo(tmp_path) |
| 999 | CAP = 200 |
| 1000 | (config_toml_path(repo)).write_text( |
| 1001 | f"[limits]\nmax_ancestors = {CAP}\n" |
| 1002 | ) |
| 1003 | |
| 1004 | # Build a shallow divergence: 50 commits each, well inside the cap. |
| 1005 | snap_id = "ff" * 32 |
| 1006 | root_cid = compute_commit_id( |
| 1007 | parent_ids=[], |
| 1008 | snapshot_id=snap_id, |
| 1009 | message="base", |
| 1010 | committed_at_iso="2026-01-01T00:00:00+00:00", |
| 1011 | author="t",) |
| 1012 | root_rec = CommitRecord( |
| 1013 | commit_id=root_cid, |
| 1014 | branch="main", |
| 1015 | snapshot_id=snap_id, |
| 1016 | message="base", |
| 1017 | committed_at=datetime.datetime(2026, 1, 1, tzinfo=datetime.timezone.utc), |
| 1018 | parent_commit_id=None, |
| 1019 | parent2_commit_id=None, |
| 1020 | author="t", |
| 1021 | metadata={}, |
| 1022 | structured_delta=None, |
| 1023 | sem_ver_bump="none", |
| 1024 | breaking_changes=[], |
| 1025 | agent_id="", |
| 1026 | model_id="", |
| 1027 | toolchain_id="", |
| 1028 | prompt_hash="", |
| 1029 | signature="", |
| 1030 | signer_key_id="", |
| 1031 | ) |
| 1032 | write_commit(repo, root_rec) |
| 1033 | |
| 1034 | def _extend(parent: str, prefix: str, n: int) -> str: |
| 1035 | tip = parent |
| 1036 | for i in range(n): |
| 1037 | msg = f"{prefix}-{i:04d}" |
| 1038 | ts = datetime.datetime(2026, 2, 1, tzinfo=datetime.timezone.utc) |
| 1039 | cid = compute_commit_id( |
| 1040 | parent_ids=[tip], |
| 1041 | snapshot_id=snap_id, |
| 1042 | message=msg, |
| 1043 | committed_at_iso=ts.isoformat(), |
| 1044 | author="t",) |
| 1045 | rec = CommitRecord( |
| 1046 | commit_id=cid, |
| 1047 | branch=prefix, |
| 1048 | snapshot_id=snap_id, |
| 1049 | message=msg, |
| 1050 | committed_at=ts, |
| 1051 | parent_commit_id=tip, |
| 1052 | parent2_commit_id=None, |
| 1053 | author="t", |
| 1054 | metadata={}, |
| 1055 | structured_delta=None, |
| 1056 | sem_ver_bump="none", |
| 1057 | breaking_changes=[], |
| 1058 | agent_id="", |
| 1059 | model_id="", |
| 1060 | toolchain_id="", |
| 1061 | prompt_hash="", |
| 1062 | signature="", |
| 1063 | signer_key_id="", |
| 1064 | ) |
| 1065 | write_commit(repo, rec) |
| 1066 | tip = cid |
| 1067 | return tip |
| 1068 | |
| 1069 | tip_a = _extend(root_cid, "xa", 50) |
| 1070 | tip_b = _extend(root_cid, "xb", 50) |
| 1071 | |
| 1072 | tracemalloc.start() |
| 1073 | tracemalloc.clear_traces() |
| 1074 | try: |
| 1075 | base = find_merge_base(repo, tip_a, tip_b) |
| 1076 | except MuseCLIError: |
| 1077 | base = None # Cap triggered — that's also a valid outcome. |
| 1078 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 1079 | tracemalloc.stop() |
| 1080 | |
| 1081 | peak_mib = peak_bytes / (1024 * 1024) |
| 1082 | assert peak_mib <= 64, ( |
| 1083 | f"find_merge_base peak {peak_mib:.1f} MiB — expected ≤ 64 MiB " |
| 1084 | f"for two 50-commit branches (cap={CAP})." |
| 1085 | ) |
| 1086 | |
| 1087 | |
| 1088 | class TestSnapshotManifest75kFiles: |
| 1089 | """build_snapshot_manifest on 75 000 files must stay under 512 MiB. |
| 1090 | |
| 1091 | The manifest dict holds only ``{rel_path: sha256_hex}`` — strings only. |
| 1092 | 75k × (60-char path + 64-char hash) ≈ 9.3 MiB for the dict alone. |
| 1093 | The peak should be dominated by the stat-cache msgpack load, not by |
| 1094 | the manifest itself. 512 MiB is a generous ceiling to catch any |
| 1095 | accidental full-file-content buffering. |
| 1096 | """ |
| 1097 | |
| 1098 | @pytest.mark.slow |
| 1099 | def test_75k_files_peak_rss_under_512_mib( |
| 1100 | self, tmp_path: pathlib.Path |
| 1101 | ) -> None: |
| 1102 | """build_snapshot_manifest on 75 000 small files stays under 512 MiB.""" |
| 1103 | root = tmp_path / "workdir" |
| 1104 | root.mkdir() |
| 1105 | muse_dir(root).mkdir() |
| 1106 | (repo_json_path(root)).write_text('{"repo_id": "bench"}') |
| 1107 | |
| 1108 | # 750 dirs × 100 files = 75 000 files, each 128 bytes. |
| 1109 | for d in range(750): |
| 1110 | dp = root / f"pkg_{d:04d}" |
| 1111 | dp.mkdir() |
| 1112 | for f in range(100): |
| 1113 | (dp / f"f_{f:03d}.py").write_bytes(b"x" * 128) |
| 1114 | |
| 1115 | tracemalloc.start() |
| 1116 | tracemalloc.clear_traces() |
| 1117 | manifest = build_snapshot_manifest(root) |
| 1118 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 1119 | tracemalloc.stop() |
| 1120 | |
| 1121 | assert len(manifest) == 75_000, ( |
| 1122 | f"Expected 75 000 files in manifest, got {len(manifest)}" |
| 1123 | ) |
| 1124 | peak_mib = peak_bytes / (1024 * 1024) |
| 1125 | assert peak_mib <= 512, ( |
| 1126 | f"build_snapshot_manifest(75k) peak {peak_mib:.1f} MiB exceeds 512 MiB. " |
| 1127 | "File content must never be loaded into memory — only stat + SHA-256." |
| 1128 | ) |
| 1129 | |
| 1130 | def test_10k_files_peak_rss_under_64_mib( |
| 1131 | self, tmp_path: pathlib.Path |
| 1132 | ) -> None: |
| 1133 | """10k-file manifest stays under 64 MiB (fast smoke for the ceiling property).""" |
| 1134 | root = tmp_path / "workdir" |
| 1135 | root.mkdir() |
| 1136 | muse_dir(root).mkdir() |
| 1137 | (repo_json_path(root)).write_text('{"repo_id": "bench"}') |
| 1138 | |
| 1139 | for d in range(100): |
| 1140 | dp = root / f"pkg_{d:03d}" |
| 1141 | dp.mkdir() |
| 1142 | for f in range(100): |
| 1143 | (dp / f"f_{f:03d}.py").write_bytes(b"y" * 64) |
| 1144 | |
| 1145 | tracemalloc.start() |
| 1146 | tracemalloc.clear_traces() |
| 1147 | manifest = build_snapshot_manifest(root) |
| 1148 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 1149 | tracemalloc.stop() |
| 1150 | |
| 1151 | assert len(manifest) == 10_000 |
| 1152 | peak_mib = peak_bytes / (1024 * 1024) |
| 1153 | assert peak_mib <= 64, ( |
| 1154 | f"build_snapshot_manifest(10k) peak {peak_mib:.1f} MiB — expected ≤ 64 MiB." |
| 1155 | ) |
| 1156 | |
| 1157 | |
| 1158 | class TestWalkCommitsBetweenCap: |
| 1159 | """walk_commits_between must truncate at its cap, never OOM. |
| 1160 | |
| 1161 | This function is used by ``muse status --json`` for ahead/behind counts. |
| 1162 | A branch 100k commits ahead of remote must return at most ``max_commits`` |
| 1163 | records and set ``truncated=True`` — it must never allocate memory |
| 1164 | proportional to the full chain depth. |
| 1165 | """ |
| 1166 | |
| 1167 | def test_truncates_at_cap_not_oom( |
| 1168 | self, tmp_path: pathlib.Path |
| 1169 | ) -> None: |
| 1170 | """Chain of 1 000 commits with cap=100 truncates, doesn't exhaust memory.""" |
| 1171 | repo = _repo(tmp_path) |
| 1172 | N = 1_000 |
| 1173 | CAP = 100 |
| 1174 | tip = _write_chain(repo, "main", N) |
| 1175 | |
| 1176 | result = walk_commits_between_result(repo, tip, max_commits=CAP) |
| 1177 | |
| 1178 | assert result["truncated"] is True, ( |
| 1179 | "Expected truncated=True for chain longer than cap" |
| 1180 | ) |
| 1181 | assert len(result["commits"]) == CAP, ( |
| 1182 | f"Expected exactly {CAP} commits, got {len(result['commits'])}" |
| 1183 | ) |
| 1184 | |
| 1185 | def test_truncation_memory_bounded( |
| 1186 | self, tmp_path: pathlib.Path |
| 1187 | ) -> None: |
| 1188 | """walk_commits_between_result peak memory is bounded by cap, not chain depth.""" |
| 1189 | repo = _repo(tmp_path) |
| 1190 | N = 2_000 |
| 1191 | CAP = 200 |
| 1192 | tip = _write_chain(repo, "main", N) |
| 1193 | |
| 1194 | tracemalloc.start() |
| 1195 | tracemalloc.clear_traces() |
| 1196 | result = walk_commits_between_result(repo, tip, max_commits=CAP) |
| 1197 | _, peak_bytes = tracemalloc.get_traced_memory() |
| 1198 | tracemalloc.stop() |
| 1199 | |
| 1200 | assert result["count"] == CAP |
| 1201 | peak_mib = peak_bytes / (1024 * 1024) |
| 1202 | assert peak_mib <= 32, ( |
| 1203 | f"walk_commits_between_result(cap={CAP}) peak {peak_mib:.1f} MiB — " |
| 1204 | "memory must be proportional to cap, not chain depth." |
| 1205 | ) |