diff options
Diffstat (limited to 'research/experiments/013-parallel-syncs')
5 files changed, 149 insertions, 3 deletions
diff --git a/research/experiments/013-parallel-syncs/2026-09-27-journal-before-085-ext4-linux-aarch64.jsonl b/research/experiments/013-parallel-syncs/2026-09-27-journal-before-085-ext4-linux-aarch64.jsonl new file mode 100644 index 0000000..5b8320d --- /dev/null +++ b/research/experiments/013-parallel-syncs/2026-09-27-journal-before-085-ext4-linux-aarch64.jsonl @@ -0,0 +1,20 @@ +{"round": 0, "store": "as it is", "commits_per_second": 362, "p50_ms": 1.26, "p90_ms": 3.98, "p99_ms": 55.11, "journal_commits": 113} +{"round": 0, "store": "no compaction", "commits_per_second": 427, "p50_ms": 1.27, "p90_ms": 3.91, "p99_ms": 36.68, "journal_commits": 44} +{"round": 0, "store": "no compaction, no growth", "commits_per_second": 541, "p50_ms": 1.27, "p90_ms": 3.17, "p99_ms": 5.49, "journal_commits": 8} +{"round": 0, "store": "compacted file sized like the old", "commits_per_second": 477, "p50_ms": 1.26, "p90_ms": 3.21, "p99_ms": 10.87, "journal_commits": 46} +{"round": 1, "store": "no compaction", "commits_per_second": 458, "p50_ms": 1.28, "p90_ms": 3.52, "p99_ms": 16.56, "journal_commits": 43} +{"round": 1, "store": "no compaction, no growth", "commits_per_second": 440, "p50_ms": 1.27, "p90_ms": 4.08, "p99_ms": 25.17, "journal_commits": 7} +{"round": 1, "store": "compacted file sized like the old", "commits_per_second": 413, "p50_ms": 1.26, "p90_ms": 3.22, "p99_ms": 25.22, "journal_commits": 48} +{"round": 1, "store": "as it is", "commits_per_second": 370, "p50_ms": 1.29, "p90_ms": 4.01, "p99_ms": 33.16, "journal_commits": 110} +{"round": 2, "store": "no compaction, no growth", "commits_per_second": 424, "p50_ms": 1.28, "p90_ms": 3.94, "p99_ms": 25.66, "journal_commits": 9} +{"round": 2, "store": "compacted file sized like the old", "commits_per_second": 461, "p50_ms": 1.26, "p90_ms": 3.3, "p99_ms": 21.71, "journal_commits": 46} +{"round": 2, "store": "as it is", "commits_per_second": 340, "p50_ms": 1.28, "p90_ms": 4.21, "p99_ms": 35.79, "journal_commits": 114} +{"round": 2, "store": "no compaction", "commits_per_second": 404, "p50_ms": 1.28, "p90_ms": 4.13, "p99_ms": 31.76, "journal_commits": 33} +{"round": 3, "store": "compacted file sized like the old", "commits_per_second": 433, "p50_ms": 1.25, "p90_ms": 3.13, "p99_ms": 25.18, "journal_commits": 46} +{"round": 3, "store": "as it is", "commits_per_second": 373, "p50_ms": 1.27, "p90_ms": 3.94, "p99_ms": 56.67, "journal_commits": 114} +{"round": 3, "store": "no compaction", "commits_per_second": 384, "p50_ms": 1.27, "p90_ms": 3.98, "p99_ms": 53.28, "journal_commits": 36} +{"round": 3, "store": "no compaction, no growth", "commits_per_second": 475, "p50_ms": 1.27, "p90_ms": 3.91, "p99_ms": 21.46, "journal_commits": 13} +{"store": "as it is", "commits": 4000, "commits_per_second": 366.0, "p50_ms": 1.275, "p90_ms": 3.995, "p99_ms": 45.45, "journal_commits": 113.5} +{"store": "no compaction", "commits": 4000, "commits_per_second": 415.5, "p50_ms": 1.275, "p90_ms": 3.9450000000000003, "p99_ms": 34.22, "journal_commits": 39.5} +{"store": "no compaction, no growth", "commits": 4000, "commits_per_second": 457.5, "p50_ms": 1.27, "p90_ms": 3.925, "p99_ms": 23.315, "journal_commits": 8.5} +{"store": "compacted file sized like the old", "commits": 4000, "commits_per_second": 447.0, "p50_ms": 1.26, "p90_ms": 3.215, "p99_ms": 23.445, "journal_commits": 46.0} diff --git a/research/experiments/013-parallel-syncs/2026-09-27-journal-ext4-linux-aarch64.jsonl b/research/experiments/013-parallel-syncs/2026-09-27-journal-ext4-linux-aarch64.jsonl new file mode 100644 index 0000000..0c14f32 --- /dev/null +++ b/research/experiments/013-parallel-syncs/2026-09-27-journal-ext4-linux-aarch64.jsonl @@ -0,0 +1,20 @@ +{"round": 0, "store": "as it is", "commits_per_second": 411, "p50_ms": 1.27, "p90_ms": 3.96, "p99_ms": 25.68, "journal_commits": 52} +{"round": 0, "store": "no compaction", "commits_per_second": 449, "p50_ms": 1.27, "p90_ms": 3.99, "p99_ms": 23.52, "journal_commits": 46} +{"round": 0, "store": "no compaction, no growth", "commits_per_second": 519, "p50_ms": 1.27, "p90_ms": 3.14, "p99_ms": 5.55, "journal_commits": 4} +{"round": 0, "store": "tail grown as commits need it", "commits_per_second": 346, "p50_ms": 1.29, "p90_ms": 4.01, "p99_ms": 26.25, "journal_commits": 117} +{"round": 1, "store": "no compaction", "commits_per_second": 360, "p50_ms": 1.28, "p90_ms": 3.94, "p99_ms": 32.97, "journal_commits": 42} +{"round": 1, "store": "no compaction, no growth", "commits_per_second": 413, "p50_ms": 1.28, "p90_ms": 4.07, "p99_ms": 26.58, "journal_commits": 18} +{"round": 1, "store": "tail grown as commits need it", "commits_per_second": 270, "p50_ms": 1.28, "p90_ms": 4.34, "p99_ms": 50.93, "journal_commits": 110} +{"round": 1, "store": "as it is", "commits_per_second": 382, "p50_ms": 1.25, "p90_ms": 3.99, "p99_ms": 26.49, "journal_commits": 40} +{"round": 2, "store": "no compaction, no growth", "commits_per_second": 463, "p50_ms": 1.27, "p90_ms": 3.96, "p99_ms": 22.29, "journal_commits": 21} +{"round": 2, "store": "tail grown as commits need it", "commits_per_second": 289, "p50_ms": 1.27, "p90_ms": 3.99, "p99_ms": 32.56, "journal_commits": 104} +{"round": 2, "store": "as it is", "commits_per_second": 356, "p50_ms": 1.27, "p90_ms": 3.93, "p99_ms": 37.21, "journal_commits": 46} +{"round": 2, "store": "no compaction", "commits_per_second": 393, "p50_ms": 1.26, "p90_ms": 4.08, "p99_ms": 32.96, "journal_commits": 41} +{"round": 3, "store": "tail grown as commits need it", "commits_per_second": 406, "p50_ms": 1.27, "p90_ms": 4.12, "p99_ms": 26.45, "journal_commits": 108} +{"round": 3, "store": "as it is", "commits_per_second": 389, "p50_ms": 1.27, "p90_ms": 4.06, "p99_ms": 27.31, "journal_commits": 44} +{"round": 3, "store": "no compaction", "commits_per_second": 392, "p50_ms": 1.26, "p90_ms": 3.4, "p99_ms": 52.8, "journal_commits": 44} +{"round": 3, "store": "no compaction, no growth", "commits_per_second": 469, "p50_ms": 1.27, "p90_ms": 3.88, "p99_ms": 22.84, "journal_commits": 15} +{"store": "as it is", "commits": 4000, "commits_per_second": 385.5, "p50_ms": 1.27, "p90_ms": 3.975, "p99_ms": 26.9, "journal_commits": 45.0} +{"store": "no compaction", "commits": 4000, "commits_per_second": 392.5, "p50_ms": 1.2650000000000001, "p90_ms": 3.965, "p99_ms": 32.965, "journal_commits": 43.0} +{"store": "no compaction, no growth", "commits": 4000, "commits_per_second": 466.0, "p50_ms": 1.27, "p90_ms": 3.92, "p99_ms": 22.564999999999998, "journal_commits": 16.5} +{"store": "tail grown as commits need it", "commits": 4000, "commits_per_second": 317.5, "p50_ms": 1.275, "p90_ms": 4.0649999999999995, "p99_ms": 29.505000000000003, "journal_commits": 109.0} diff --git a/research/experiments/013-parallel-syncs/2026-09-27-store-variants-085-ext4-linux-aarch64.jsonl b/research/experiments/013-parallel-syncs/2026-09-27-store-variants-085-ext4-linux-aarch64.jsonl new file mode 100644 index 0000000..5e26b0f --- /dev/null +++ b/research/experiments/013-parallel-syncs/2026-09-27-store-variants-085-ext4-linux-aarch64.jsonl @@ -0,0 +1,36 @@ +{"round": 0, "store": "as it is", "posts_per_second": 23632.25, "p50_us": 1984, "p99_us": 21504, "max_us": 61440, "errors": 0} +{"round": 0, "store": "no compaction", "posts_per_second": 21552.25, "p50_us": 2176, "p99_us": 17408, "max_us": 147456, "errors": 0} +{"round": 0, "store": "no compaction, no growth", "posts_per_second": 24320.25, "p50_us": 1984, "p99_us": 12800, "max_us": 61440, "errors": 0} +{"round": 0, "store": "tail grown as commits need it", "posts_per_second": 21392.25, "p50_us": 2176, "p99_us": 16384, "max_us": 69632, "errors": 0} +{"round": 1, "store": "no compaction", "posts_per_second": 21942.75, "p50_us": 2176, "p99_us": 13312, "max_us": 65536, "errors": 0} +{"round": 1, "store": "no compaction, no growth", "posts_per_second": 22688.25, "p50_us": 1984, "p99_us": 15360, "max_us": 163840, "errors": 0} +{"round": 1, "store": "tail grown as commits need it", "posts_per_second": 21433.5, "p50_us": 2176, "p99_us": 14336, "max_us": 73728, "errors": 0} +{"round": 1, "store": "as it is", "posts_per_second": 24960.25, "p50_us": 1984, "p99_us": 12800, "max_us": 73728, "errors": 0} +{"round": 2, "store": "no compaction, no growth", "posts_per_second": 23088.0, "p50_us": 2176, "p99_us": 12800, "max_us": 53248, "errors": 0} +{"round": 2, "store": "tail grown as commits need it", "posts_per_second": 22016.25, "p50_us": 2176, "p99_us": 15360, "max_us": 65536, "errors": 0} +{"round": 2, "store": "as it is", "posts_per_second": 23760.25, "p50_us": 1984, "p99_us": 12288, "max_us": 90112, "errors": 0} +{"round": 2, "store": "no compaction", "posts_per_second": 21280.25, "p50_us": 2176, "p99_us": 14336, "max_us": 59392, "errors": 0} +{"round": 3, "store": "tail grown as commits need it", "posts_per_second": 22081.25, "p50_us": 2176, "p99_us": 13824, "max_us": 65536, "errors": 0} +{"round": 3, "store": "as it is", "posts_per_second": 22594.75, "p50_us": 2176, "p99_us": 12288, "max_us": 81920, "errors": 0} +{"round": 3, "store": "no compaction", "posts_per_second": 21104.25, "p50_us": 2176, "p99_us": 21504, "max_us": 139264, "errors": 0} +{"round": 3, "store": "no compaction, no growth", "posts_per_second": 23419.25, "p50_us": 2176, "p99_us": 13312, "max_us": 57344, "errors": 0} +{"round": 4, "store": "as it is", "posts_per_second": 22673.25, "p50_us": 2048, "p99_us": 15360, "max_us": 81920, "errors": 0} +{"round": 4, "store": "no compaction", "posts_per_second": 23472.25, "p50_us": 2048, "p99_us": 14336, "max_us": 69632, "errors": 0} +{"round": 4, "store": "no compaction, no growth", "posts_per_second": 23881.5, "p50_us": 1984, "p99_us": 16384, "max_us": 61440, "errors": 0} +{"round": 4, "store": "tail grown as commits need it", "posts_per_second": 17632.25, "p50_us": 2304, "p99_us": 12800, "max_us": 589824, "errors": 0} +{"round": 5, "store": "no compaction", "posts_per_second": 19040.25, "p50_us": 2176, "p99_us": 14336, "max_us": 655360, "errors": 0} +{"round": 5, "store": "no compaction, no growth", "posts_per_second": 23552.25, "p50_us": 2048, "p99_us": 18432, "max_us": 59392, "errors": 0} +{"round": 5, "store": "tail grown as commits need it", "posts_per_second": 22192.0, "p50_us": 2176, "p99_us": 15872, "max_us": 73728, "errors": 0} +{"round": 5, "store": "as it is", "posts_per_second": 20928.25, "p50_us": 2176, "p99_us": 21504, "max_us": 77824, "errors": 0} +{"round": 6, "store": "no compaction, no growth", "posts_per_second": 24608.25, "p50_us": 1984, "p99_us": 12800, "max_us": 61440, "errors": 0} +{"round": 6, "store": "tail grown as commits need it", "posts_per_second": 19088.25, "p50_us": 2176, "p99_us": 15872, "max_us": 589824, "errors": 0} +{"round": 6, "store": "as it is", "posts_per_second": 22576.25, "p50_us": 2048, "p99_us": 20480, "max_us": 77824, "errors": 0} +{"round": 6, "store": "no compaction", "posts_per_second": 23184.25, "p50_us": 1984, "p99_us": 16384, "max_us": 73728, "errors": 0} +{"round": 7, "store": "tail grown as commits need it", "posts_per_second": 22080.25, "p50_us": 2176, "p99_us": 14336, "max_us": 69632, "errors": 0} +{"round": 7, "store": "as it is", "posts_per_second": 23088.25, "p50_us": 2048, "p99_us": 21504, "max_us": 65536, "errors": 0} +{"round": 7, "store": "no compaction", "posts_per_second": 23051.75, "p50_us": 2048, "p99_us": 14336, "max_us": 65536, "errors": 0} +{"round": 7, "store": "no compaction, no growth", "posts_per_second": 22586.5, "p50_us": 2048, "p99_us": 19456, "max_us": 57344, "errors": 0} +{"store": "as it is", "rounds": 8, "posts_per_second_median": 22880.75, "p99_us_median": 17920.0, "max_us": 90112} +{"store": "no compaction", "rounds": 8, "posts_per_second_median": 21747.5, "p99_us_median": 14336.0, "max_us": 655360} +{"store": "no compaction, no growth", "rounds": 8, "posts_per_second_median": 23485.75, "p99_us_median": 14336.0, "max_us": 163840} +{"store": "tail grown as commits need it", "rounds": 8, "posts_per_second_median": 21724.875, "p99_us_median": 14848.0, "max_us": 589824} diff --git a/research/experiments/013-parallel-syncs/journal.py b/research/experiments/013-parallel-syncs/journal.py new file mode 100644 index 0000000..5f49095 --- /dev/null +++ b/research/experiments/013-parallel-syncs/journal.py @@ -0,0 +1,66 @@ +#!/usr/bin/env python3 +"""The tree store's commits under each store variant of variants.py, without +HTTP: latency percentiles of research/experiments/010-one-sync-commit +/commits.c, and how many ext4 journal commits (jbd2 transactions, read from +/proc/fs/jbd2) each run caused. Rounds rotate the variants' order.""" +import argparse +import json +import re +import shutil +import statistics +import subprocess +import sys +import tempfile +from pathlib import Path + +import variants + +HERE = Path(__file__).resolve().parent +ROOT = HERE.parents[2] +COMMITS = HERE.parent / '010-one-sync-commit' / 'commits.c' + + +def transactions(device): + return int(re.match(r'(\d+) transactions', (Path('/proc/fs/jbd2') / device / 'info').read_text()).group(1)) + + +def main(): + parser = argparse.ArgumentParser() + parser.add_argument('--directory', type=Path, default=Path('/var/tmp'), help='on the device to measure') + parser.add_argument('--journal', default='mmcblk0p2-8', help='its /proc/fs/jbd2 entry') + parser.add_argument('--rounds', type=int, default=4) + parser.add_argument('--commits', type=int, default=4000) + args = parser.parse_args() + with tempfile.TemporaryDirectory() as work: + work = Path(work) + binaries = {} + for number, (name, patches) in enumerate(variants.PATCHES.items()): + source = (ROOT / 'store' / 'store-tree.c').read_text() + for old, new in patches: + assert old in source, old + source = source.replace(old, new) + (work / f'store-{number}.c').write_text(source) + binaries[name] = work / f'commits-{number}' + subprocess.run(['cc', '-O2', '-std=c17', f'-I{ROOT / "core"}', '-o', str(binaries[name]), str(COMMITS), + str(work / f'store-{number}.c'), '-lpthread'], check=True) + names, runs = list(binaries), {name: [] for name in binaries} + for round_ in range(args.rounds): + for name in names[round_ % len(names):] + names[:round_ % len(names)]: + store = Path(tempfile.mkdtemp(dir=args.directory, prefix='pure-journal-')) + shutil.rmtree(store) + try: + before = transactions(args.journal) + out = subprocess.run([str(binaries[name]), str(store), str(args.commits)], capture_output=True, + text=True, check=True) + measured = {**json.loads(out.stdout), 'journal_commits': transactions(args.journal) - before} + finally: + shutil.rmtree(store, ignore_errors=True) + runs[name].append(measured) + print(json.dumps({'round': round_, 'store': name, **measured}), flush=True) + for name in names: + print(json.dumps({'store': name, 'commits': args.commits, **{key: statistics.median(r[key] for r in runs[name]) + for key in ('commits_per_second', 'p50_ms', 'p90_ms', 'p99_ms', 'journal_commits')}})) + + +if __name__ == '__main__': + sys.exit(main()) diff --git a/research/experiments/013-parallel-syncs/variants.py b/research/experiments/013-parallel-syncs/variants.py index 2c48ab6..ee49d2a 100644 --- a/research/experiments/013-parallel-syncs/variants.py +++ b/research/experiments/013-parallel-syncs/variants.py @@ -1,9 +1,10 @@ #!/usr/bin/env python3 """Where the tree store's extra sync work goes (docs/research/084-parallel-syncs.md). -Builds pure-serve with three stores from store/store-tree.c: as it is; with no -compaction; and with no compaction and a 64 MiB tail written at creation (no -tail growth during a run). Then durable score posts (64 connections), the +Builds pure-serve with stores from store/store-tree.c: as it is; with no +compaction; with no compaction and a 64 MiB tail written at creation (no tail +growth during a run); and as before 085, compacted files getting only 256 KiB +of zeros and commits growing the tail as they need it. Then durable score posts (64 connections), the builds in rotated order per round, each on a fresh store after 64 warm-up posts. Prints one JSON line per run and a summary. """ @@ -25,6 +26,9 @@ PATCHES = { 'no compaction': [('enum { COMPACT_SLACK = 1048576 };', 'enum { COMPACT_SLACK = 1 << 30 };')], 'no compaction, no growth': [('enum { COMPACT_SLACK = 1048576 };', 'enum { COMPACT_SLACK = 1 << 30 };'), ('TAIL_STEP = 262144', 'TAIL_STEP = 67108864')], + # Before 085: a compacted file got 256 KiB of zeros, and commits grew the tail as they needed it. + 'tail grown as commits need it': [('zero_fill(fd, head->end, cycle_end(head, replaced));', + 'zero_fill(fd, head->end, tail_end(head->end));')], } |