Add TP2 prefill serving-path smoke experiment

runs/frontier-tp2-prefill-serving-v0/run_request.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+"""Issue one non-streaming completion request and record wall/usage."""
+
+from __future__ import annotations
+
+import argparse
+import json
+import time
+import urllib.request
+from pathlib import Path
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--port", type=int, required=True)
+    parser.add_argument("--request", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    parser.add_argument("--timeout-seconds", type=float, default=1800)
+    return parser.parse_args()
+
+
+def main() -> None:
+    args = parse_args()
+    body = json.loads(args.request.read_text())
+    expected_input = len(body["prompt"])
+    expected_output = int(body["max_tokens"])
+    request = urllib.request.Request(
+        f"http://127.0.0.1:{args.port}/v1/completions",
+        data=json.dumps(body, separators=(",", ":")).encode(),
+        headers={"Content-Type": "application/json"},
+        method="POST",
+    )
+    started = time.monotonic()
+    with urllib.request.urlopen(
+        request, timeout=args.timeout_seconds
+    ) as response:
+        payload = json.load(response)
+    wall_ms = (time.monotonic() - started) * 1000
+    usage = payload.get("usage") or {}
+    observed = (
+        int(usage.get("prompt_tokens", -1)),
+        int(usage.get("completion_tokens", -1)),
+    )
+    if observed != (expected_input, expected_output):
+        raise ValueError(
+            f"usage mismatch: expected {expected_input}+{expected_output}, "
+            f"observed {observed[0]}+{observed[1]}"
+        )
+    result = {
+        "wall_ms": wall_ms,
+        "input_tokens": observed[0],
+        "output_tokens": observed[1],
+        "usage": usage,
+    }
+    args.output.parent.mkdir(parents=True, exist_ok=True)
+    args.output.write_text(json.dumps(result, indent=2, sort_keys=True) + "\n")
+    print(json.dumps(result, sort_keys=True), flush=True)
+
+
+if __name__ == "__main__":
+    main()