[Test] Batch Invariant: Rename and organize tests (#27421)

Signed-off-by: yewentao256 <zhyanwentao@126.com>

tests/v1/determinism/conftest.py

@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def enable_batch_invariant_mode(monkeypatch: pytest.MonkeyPatch):
+    """Automatically enable batch invariant kernel overrides for all tests."""
+    monkeypatch.setenv("VLLM_BATCH_INVARIANT", "1")
+    yield

tests/v1/determinism/test_batch_invariance.py

@@ -6,66 +6,9 @@ import random
 
 import pytest
 import torch
+from utils import _extract_step_logprobs, _random_prompt, skip_unsupported
 
 from vllm import LLM, SamplingParams
-from vllm.platforms import current_platform
-
-skip_unsupported = pytest.mark.skipif(
-    not (current_platform.is_cuda() and current_platform.has_device_capability(90)),
-    reason="Requires CUDA and >= Hopper (SM90)",
-)
-
-
-@pytest.fixture(autouse=True)
-def enable_batch_invariant_mode(monkeypatch: pytest.MonkeyPatch):
-    """Automatically enable batch invariant kernel overrides for all tests."""
-    monkeypatch.setenv("VLLM_BATCH_INVARIANT", "1")
-    yield
-
-
-def _random_prompt(min_words: int = 1024, max_words: int = 1024 * 2) -> str:
-    # Generate more realistic prompts that will actually produce varied tokens
-    # Use a mix of common English text patterns
-
-    prompt_templates = [
-        # Question-answer style
-        "Question: What is the capital of France?\nAnswer: The capital of France is",
-        "Q: How does photosynthesis work?\nA: Photosynthesis is the process by which",
-        "User: Can you explain quantum mechanics?\nAssistant: Quantum mechanics is",
-        # Story/narrative style
-        "Once upon a time in a distant galaxy, there lived",
-        "The old man walked slowly down the street, remembering",
-        "In the year 2157, humanity finally discovered",
-        # Technical/code style
-        "To implement a binary search tree in Python, first we need to",
-        "The algorithm works by iterating through the array and",
-        "Here's how to optimize database queries using indexing:",
-        # Factual/informative style
-        "The Renaissance was a period in European history that",
-        "Climate change is caused by several factors including",
-        "The human brain contains approximately 86 billion neurons which",
-        # Conversational style
-        "I've been thinking about getting a new laptop because",
-        "Yesterday I went to the store and bought",
-        "My favorite thing about summer is definitely",
-    ]
-
-    # Pick a random template
-    base_prompt = random.choice(prompt_templates)
-
-    if max_words < min_words:
-        max_words = min_words
-    target_words = random.randint(min_words, max_words)
-
-    if target_words > 50:
-        # For longer prompts, repeat context
-        padding_text = (
-            " This is an interesting topic that deserves more explanation. "
-            * (target_words // 50)
-        )
-        base_prompt = base_prompt + padding_text
-
-    return base_prompt
 
 
 @skip_unsupported
@@ -204,22 +147,6 @@ def test_v1_generation_is_deterministic_across_batch_sizes_with_needle(
                 llm_bsN.shutdown()
 
 
-def _extract_step_logprobs(request_output):
-    if getattr(request_output, "outputs", None):
-        inner = request_output.outputs[0]
-        if hasattr(inner, "logprobs") and inner.logprobs is not None:
-            t = torch.tensor(
-                [
-                    inner.logprobs[i][tid].logprob
-                    for i, tid in enumerate(inner.token_ids)
-                ],
-                dtype=torch.float32,
-            )
-            return t, inner.token_ids
-
-    return None, None
-
-
 @skip_unsupported
 @pytest.mark.parametrize(
     "backend",

tests/v1/determinism/test_online_batch_invariance.py

@@ -0,0 +1,161 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+"""
+HTTP-based batch invariance test: send requests to a running
+vLLM server and compare BS=1 vs BS=N results (tokens and per-step logprobs).
+
+Environment variables:
+  - VLLM_TEST_MODEL: served model name (e.g., Qwen/Qwen3-1.7B / DeepSeek-R1)
+  - VLLM_TP_SIZE: tensor parallelism size (e.g., 4)
+
+"""
+
+import os
+import random
+import sys
+from typing import Any
+
+import openai
+from utils import _random_prompt, skip_unsupported
+
+from tests.utils import RemoteOpenAIServer
+
+
+def _request_completion(
+    client: openai.OpenAI,
+    model: str,
+    prompt: Any,
+    sp: dict[str, Any],
+    max_retries: int = 3,
+    retry_backoff: float = 0.5,
+) -> dict[str, Any] | None:
+    payload: dict[str, Any] = {"model": model, "prompt": prompt}
+    payload.update(sp)
+
+    for attempt in range(max_retries + 1):
+        try:
+            completion = client.completions.create(**payload)
+            # Convert to plain dict so downstream logic can keep using
+            # dict-style access just like with raw HTTP JSON.
+            return completion.model_dump()
+        except Exception as e:  # pragma: no cover
+            if attempt < max_retries:
+                import time as _t
+
+                _t.sleep(retry_backoff * (2**attempt))
+                continue
+            sys.stderr.write(f"Error: {e}\n")
+            return None
+    return None
+
+
+def _extract_tokens_and_logprobs(
+    choice: dict[str, Any],
+) -> tuple[list[Any], list[float] | None]:
+    tokens: list[Any] = []
+    token_logprobs: list[float] | None = None
+    lp = choice.get("logprobs")
+    if lp and isinstance(lp, dict):
+        tokens = lp.get("token_ids") or lp.get("tokens") or []
+        token_logprobs = lp.get("token_logprobs", None)
+    return tokens, token_logprobs
+
+
+def _compare_bs1_vs_bsn_single_process(
+    prompts: list[str],
+    sp_kwargs: dict[str, Any],
+    client: openai.OpenAI,
+    model_name: str,
+) -> None:
+    # BS=1
+    bs1_tokens_per_prompt: list[list[Any]] = []
+    bs1_logprobs_per_prompt: list[list[float] | None] = []
+    for p in prompts:
+        resp = _request_completion(client, model_name, p, sp_kwargs)
+        if resp is None or not resp.get("choices"):
+            raise AssertionError("BS=1 empty/failed response")
+        choice = resp["choices"][0]
+        toks, lps = _extract_tokens_and_logprobs(choice)
+        if lps is None:
+            raise AssertionError(
+                "logprobs not returned; ensure server supports 'logprobs'"
+            )
+        bs1_tokens_per_prompt.append(list(toks))
+        bs1_logprobs_per_prompt.append(list(lps))
+
+    # BS=N
+    bsN_tokens_per_prompt: list[list[Any]] = [None] * len(prompts)  # type: ignore[list-item]
+    bsN_logprobs_per_prompt: list[list[float] | None] = [None] * len(prompts)
+    resp = _request_completion(client, model_name, prompts, sp_kwargs)
+    if resp is None or not resp.get("choices"):
+        raise AssertionError("BS=N empty/failed batched response")
+    choices = resp.get("choices", [])
+    if len(choices) != len(prompts):
+        raise AssertionError(
+            f"BS=N choices length {len(choices)} != num prompts {len(prompts)}"
+        )
+    for idx, choice in enumerate(choices):
+        toks, lps = _extract_tokens_and_logprobs(choice)
+        if lps is None:
+            raise AssertionError(f"BS=N missing logprobs for prompt {idx}")
+        bsN_tokens_per_prompt[idx] = list(toks)
+        bsN_logprobs_per_prompt[idx] = list(lps)
+
+    # compare
+    for i, (tokens_bs1, tokens_bsN, logprobs_bs1, logprobs_bsN) in enumerate(
+        zip(
+            bs1_tokens_per_prompt,
+            bsN_tokens_per_prompt,
+            bs1_logprobs_per_prompt,
+            bsN_logprobs_per_prompt,
+        )
+    ):
+        if tokens_bs1 != tokens_bsN:
+            raise AssertionError(
+                f"Prompt {i} (sampling): Different tokens sampled. "
+                f"BS=1 tokens: {tokens_bs1} BS=N tokens: {tokens_bsN}"
+            )
+        if logprobs_bs1 is None or logprobs_bsN is None:
+            raise AssertionError(f"Prompt {i}: Missing logprobs in one of the runs")
+        if len(logprobs_bs1) != len(logprobs_bsN):
+            raise AssertionError(
+                f"Prompt {i}: Different number of steps: "
+                f"{len(logprobs_bs1)} (BS=1) vs {len(logprobs_bsN)} (BS=N)."
+            )
+        for t, (a, b) in enumerate(zip(logprobs_bs1, logprobs_bsN)):
+            if a != b:
+                diff = abs(a - b)
+                raise AssertionError(
+                    f"Prompt {i} Step {t}: Bitwise mismatch "
+                    f"(abs diff={diff:.6e}). "
+                    f"BS=1 tokens: {tokens_bs1} BS=N tokens: {tokens_bsN}"
+                )
+
+
+@skip_unsupported
+def test_logprobs_bitwise_batch_invariance_bs1_vs_bsN():
+    random.seed(int(os.getenv("VLLM_TEST_SEED", "12345")))
+    model_name = os.getenv("VLLM_TEST_MODEL", "Qwen/Qwen3-1.7B")
+    prompts_all = [_random_prompt(10, 50) for _ in range(32)]
+
+    sp_kwargs: dict[str, Any] = {
+        "temperature": 0.6,
+        "top_p": 1.0,
+        "max_tokens": 8,
+        "seed": 42,
+        "logprobs": 5,
+    }
+
+    tp_size = os.getenv("VLLM_TP_SIZE", "1")
+    server_args: list[str] = []
+    if tp_size:
+        server_args += ["-tp", tp_size]
+
+    with RemoteOpenAIServer(model_name, server_args) as server:
+        client = server.get_client()
+        _compare_bs1_vs_bsn_single_process(
+            prompts=prompts_all,
+            sp_kwargs=sp_kwargs,
+            client=client,
+            model_name=model_name,
+        )

tests/v1/determinism/test_rms_norm_batch_invariant.py

@@ -9,15 +9,10 @@ with the standard CUDA-based implementation to ensure numerical accuracy.
 
 import pytest
 import torch
+from utils import skip_unsupported
 
 from vllm.model_executor.layers.batch_invariant import rms_norm as triton_rms_norm
 from vllm.model_executor.layers.layernorm import RMSNorm
-from vllm.platforms import current_platform
-
-skip_unsupported = pytest.mark.skipif(
-    not (current_platform.is_cuda() and current_platform.has_device_capability(90)),
-    reason="Requires CUDA and >= Hopper (SM90)",
-)
 
 
 @skip_unsupported

tests/v1/determinism/utils.py

@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+import random
+
+import pytest
+import torch
+
+from vllm.platforms import current_platform
+
+skip_unsupported = pytest.mark.skipif(
+    not (current_platform.is_cuda() and current_platform.has_device_capability(90)),
+    reason="Requires CUDA and >= Hopper (SM90)",
+)
+
+
+def _random_prompt(min_words: int = 1024, max_words: int = 1024 * 2) -> str:
+    # Generate more realistic prompts that will actually produce varied tokens
+    # Use a mix of common English text patterns
+
+    prompt_templates = [
+        # Question-answer style
+        "Question: What is the capital of France?\nAnswer: The capital of France is",
+        "Q: How does photosynthesis work?\nA: Photosynthesis is the process by which",
+        "User: Can you explain quantum mechanics?\nAssistant: Quantum mechanics is",
+        # Story/narrative style
+        "Once upon a time in a distant galaxy, there lived",
+        "The old man walked slowly down the street, remembering",
+        "In the year 2157, humanity finally discovered",
+        # Technical/code style
+        "To implement a binary search tree in Python, first we need to",
+        "The algorithm works by iterating through the array and",
+        "Here's how to optimize database queries using indexing:",
+        # Factual/informative style
+        "The Renaissance was a period in European history that",
+        "Climate change is caused by several factors including",
+        "The human brain contains approximately 86 billion neurons which",
+        # Conversational style
+        "I've been thinking about getting a new laptop because",
+        "Yesterday I went to the store and bought",
+        "My favorite thing about summer is definitely",
+    ]
+
+    # Pick a random template
+    base_prompt = random.choice(prompt_templates)
+
+    if max_words < min_words:
+        max_words = min_words
+    target_words = random.randint(min_words, max_words)
+
+    if target_words > 50:
+        # For longer prompts, repeat context
+        padding_text = (
+            " This is an interesting topic that deserves more explanation. "
+            * (target_words // 50)
+        )
+        base_prompt = base_prompt + padding_text
+
+    return base_prompt
+
+
+def _extract_step_logprobs(request_output):
+    if getattr(request_output, "outputs", None):
+        inner = request_output.outputs[0]
+        if hasattr(inner, "logprobs") and inner.logprobs is not None:
+            t = torch.tensor(
+                [
+                    inner.logprobs[i][tid].logprob
+                    for i, tid in enumerate(inner.token_ids)
+                ],
+                dtype=torch.float32,
+            )
+            return t, inner.token_ids
+
+    return None, None