1 files changed, 63 insertions, 0 deletions
diff --git a/research/experiments/010-one-sync-commit/run.py b/research/experiments/010-one-sync-commit/run.py
new file mode 100644
index 0000000..9a01c07
--- /dev/null
+++ b/research/experiments/010-one-sync-commit/run.py
@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+"""Commit cost on the store's device (see docs/research/076-one-sync-commit.md).
+
+Runs probe.c (the ways of making a small commit durable) and commits.c (tree
+store commit latency) built against the two-sync store of --before and the
+current one, alternating their order per round so device drift reaches both
+alike. Prints one JSON document.
+"""
+import argparse
+import json
+import shutil
+import subprocess
+import sys
+import tempfile
+from pathlib import Path
+
+HERE = Path(__file__).resolve().parent
+ROOT = HERE.parents[2]
+PURE = ROOT / 'prototypes' / 'connections'
+
+
+def build(output, sources):
+    subprocess.run(['cc', '-O2', '-std=c17', f'-I{PURE}', '-o', str(output)] + [str(s) for s in sources] + ['-lpthread'],
+                   check=True)
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--directory', type=Path, default=Path('/var/tmp'), help='on the device to measure')
+    parser.add_argument('--before', default='ad2197c', help='a revision with the two-sync commit')
+    parser.add_argument('--rounds', type=int, default=3)
+    parser.add_argument('--commits', type=int, default=200)
+    args = parser.parse_args()
+    with tempfile.TemporaryDirectory() as work:
+        work = Path(work)
+        before = work / 'store-tree-before.c'
+        before.write_text(subprocess.run(['git', '-C', str(ROOT), 'show', f'{args.before}:prototypes/connections/store-tree.c'],
+                                         capture_output=True, text=True, check=True).stdout)
+        build(work / 'probe', [HERE / 'probe.c'])
+        builds = {'two syncs': work / 'commits-before', 'one sync': work / 'commits-after'}
+        build(builds['two syncs'], [HERE / 'commits.c', before])
+        build(builds['one sync'], [HERE / 'commits.c', PURE / 'store-tree.c'])
+        results = {'rounds': []}
+        for round_ in range(args.rounds):
+            probe = subprocess.run([str(work / 'probe'), str(args.directory)], capture_output=True, text=True, check=True)
+            measured = {'probe': [json.loads(line) for line in probe.stdout.splitlines()], 'commits': {}}
+            names = list(builds) if round_ % 2 == 0 else list(builds)[::-1]
+            for name in names:
+                store = Path(tempfile.mkdtemp(dir=args.directory, prefix='pure-commit-cost-'))
+                shutil.rmtree(store)
+                try:
+                    run = subprocess.run([str(builds[name]), str(store), str(args.commits)], capture_output=True, text=True,
+                                         check=True)
+                    measured['commits'][name] = json.loads(run.stdout)
+                finally:
+                    shutil.rmtree(store, ignore_errors=True)
+            results['rounds'].append(measured)
+            print(json.dumps(measured), file=sys.stderr, flush=True)
+        print(json.dumps(results, indent=1))
+
+
+if __name__ == '__main__':
+    sys.exit(main())