Files
xserv/tools/bench/pp_time.py
Gahow Wang d5dcf1a5ab bench: PP harness (xserv --pp vs llama.cpp -sm layer)
runner/servers: add --pp for both engines (xserv --pp N; llama.cpp
-sm layer over N GPUs). New drivers: pp_final.sh (sequential latency +
per-GPU VRAM + byte-exact correctness), pp_diag.sh (single x2 vs pp4 x2
determinism control), pp_quality_full.sh / pp_llama_47.sh (AIME+GSM8K
matrix, xserv on 0-3 || llama on 4-7), summarize_pp/summarize_fullq,
pp_time.py latency probe.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-05-29 18:45:59 +08:00

45 lines
1.3 KiB
Python

"""Tiny single-stream latency probe over the OpenAI HTTP API.
Usage: python3 pp_time.py BASE_URL "PROMPT"
Prints: TTFT_ms=.. TPOT_ms=.. tok_full=.. tok_s=..
TTFT ~ wall time of a max_tokens=1 request (prefill + 1 token).
TPOT ~ (t_full - t_1) / (tokens_full - tokens_1), using the server's reported
completion_tokens so it is exact even if generation stops early.
"""
import json
import sys
import time
import urllib.request
base = sys.argv[1].rstrip("/")
prompt = sys.argv[2]
def req(max_tokens):
body = json.dumps({
"model": "qwen3-8b",
"messages": [{"role": "user", "content": prompt}],
"max_tokens": max_tokens,
"temperature": 0,
"stream": False,
}).encode()
r = urllib.request.Request(base + "/v1/chat/completions", body,
{"Content-Type": "application/json"})
t = time.time()
d = json.load(urllib.request.urlopen(r, timeout=600))
dt = time.time() - t
ct = d.get("usage", {}).get("completion_tokens")
return dt, ct
t1, c1 = req(1)
tF, cF = req(160)
ttft = t1 * 1000.0
denom = (cF - c1) if (cF and c1 and cF > c1) else None
if denom:
tpot = (tF - t1) / denom * 1000.0
print(f"TTFT_ms={ttft:.1f} TPOT_ms={tpot:.2f} tok_full={cF} tok_s={1000.0/tpot:.1f}")
else:
print(f"TTFT_ms={ttft:.1f} TPOT_ms=nan tok_full={cF} tok_s=nan")