1 files changed, 76 insertions, 0 deletions
diff --git a/research/experiments/026-apps-on-one-host/memory.py b/research/experiments/026-apps-on-one-host/memory.py
new file mode 100644
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+++ b/research/experiments/026-apps-on-one-host/memory.py
@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+"""What an app costs a host (docs/design/017): pure-serve with N apps of the
+scoreboard (benchmarks/http/scores.aup), each written once and read once
+(its store opened, its snapshot published, a reader of it used), in RAM;
+then the host's own memory (smaps_rollup's Private_Dirty, RSS, PSS) and
+threads. Beside it, one pure-serve of one app (--module) the same way: the
+process an app costs when each app is a process.
+
+memory.py SERVE [N ...]
+"""
+import http.client
+import json
+import select
+import shutil
+import subprocess
+import sys
+import tempfile
+from pathlib import Path
+
+HERE = Path(__file__).resolve().parent
+ROOT = HERE.parents[2]
+AUP = ROOT.parent / 'aup' / 'build' / 'aup'
+
+
+def used(pid):
+    fields = {}
+    for line in Path(f'/proc/{pid}/smaps_rollup').read_text().splitlines()[1:]:
+        name, value = line.split(':')
+        fields[name] = int(value.split()[0])
+    threads = int(Path(f'/proc/{pid}/status').read_text().split('Threads:')[1].split()[0])
+    return {'private_dirty_kib': fields['Private_Dirty'], 'rss_kib': fields['Rss'], 'pss_kib': fields['Pss'],
+            'threads': threads}
+
+
+def touched(port, prefixes):
+    connection = http.client.HTTPConnection('127.0.0.1', port, timeout=30)
+    for prefix in prefixes:
+        for method, path, body in (('POST', f'{prefix}/inputs/score?points=1', b'k'), ('GET', f'{prefix}/views/total', None)):
+            connection.request(method, path, body, {'Content-Length': str(len(body))} if body else {})
+            answer = connection.getresponse()
+            answer.read()
+            assert answer.status == 200, (path, answer.status)
+    connection.close()
+
+
+def measured(args, prefixes):
+    process = subprocess.Popen([*map(str, args), '--port', '0'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    select.select([process.stdout], [], [], 30)
+    info = json.loads(process.stdout.readline())
+    touched(info['port'], prefixes)
+    result = used(process.pid)
+    process.terminate()
+    process.communicate(timeout=60)
+    return result
+
+
+def main():
+    serve = Path(sys.argv[1]).resolve()
+    counts = [int(n) for n in sys.argv[2:]] or [1, 10, 100]
+    work = Path(tempfile.mkdtemp(prefix='pure-apps-memory-', dir='/dev/shm'))
+    try:
+        module = work / 'scores.pmod'
+        subprocess.run([str(AUP), 'build', str(ROOT / 'benchmarks' / 'http' / 'scores.aup'), '-o', str(module)], check=True)
+        one = measured([serve, '--module', module, '--store', work / 'one', '--threads', 1], [''])
+        print(json.dumps({'way': 'process', 'apps': 1, **one}), flush=True)
+        for n in counts:
+            manifest = work / f'apps-{n}.conf'
+            manifest.write_text(''.join(f'app{i} {module} {work / f"store-{n}-{i}"}\n' for i in range(n)))
+            host = measured([serve, '--apps', manifest, '--threads', 1, '--workers', 2], [f'/app{i}' for i in range(n)])
+            print(json.dumps({'way': 'host', 'apps': n, **host}), flush=True)
+    finally:
+        shutil.rmtree(work)
+
+
+if __name__ == '__main__':
+    main()