utils.py 27.8 KB
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# SPDX-License-Identifier: Apache-2.0

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import asyncio
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import copy
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import functools
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import os
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import signal
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import subprocess
import sys
import time
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import warnings
from contextlib import contextmanager
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from pathlib import Path
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from typing import Any, Callable, Dict, List, Optional, Type, Union
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import openai
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import pytest
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import requests
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import torch
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import torch.nn.functional as F
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from openai.types.completion import Completion
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from typing_extensions import ParamSpec
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import vllm.envs as envs
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from tests.models.utils import TextTextLogprobs
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from vllm.distributed import (ensure_model_parallel_initialized,
                              init_distributed_environment)
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from vllm.engine.arg_utils import AsyncEngineArgs
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from vllm.entrypoints.openai.cli_args import make_arg_parser
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from vllm.model_executor.model_loader.loader import get_model_loader
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from vllm.platforms import current_platform
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from vllm.transformers_utils.tokenizer import get_tokenizer
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from vllm.utils import (FlexibleArgumentParser, GB_bytes,
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                        cuda_device_count_stateless, get_open_port)
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import vllm.envs as envs
import os


models_path_prefix = os.getenv('VLLM_OPTEST_MODELS_PATH') or os.getenv("OPTEST_MODELS_PATH")
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urls_port = int(os.getenv('VLLM_OPTEST_URLS_PORT', '8000'))
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if current_platform.is_rocm():
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    from amdsmi import (amdsmi_get_gpu_vram_usage,
                        amdsmi_get_processor_handles, amdsmi_init,
                        amdsmi_shut_down)

    @contextmanager
    def _nvml():
        try:
            amdsmi_init()
            yield
        finally:
            amdsmi_shut_down()
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elif current_platform.is_cuda():
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    from vllm.third_party.pynvml import (nvmlDeviceGetHandleByIndex,
                                         nvmlDeviceGetMemoryInfo, nvmlInit,
                                         nvmlShutdown)
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    @contextmanager
    def _nvml():
        try:
            nvmlInit()
            yield
        finally:
            nvmlShutdown()
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else:

    @contextmanager
    def _nvml():
        yield
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VLLM_PATH = Path(__file__).parent.parent
"""Path to root of the vLLM repository."""
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class RemoteOpenAIServer:
    DUMMY_API_KEY = "token-abc123"  # vLLM's OpenAI server does not need API key
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    def __init__(self,
                 model: str,
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                 vllm_serve_args: List[str],
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                 *,
                 env_dict: Optional[Dict[str, str]] = None,
                 auto_port: bool = True,
                 max_wait_seconds: Optional[float] = None) -> None:
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        if auto_port:
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            if "-p" in vllm_serve_args or "--port" in vllm_serve_args:
                raise ValueError("You have manually specified the port "
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                                 "when `auto_port=True`.")

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            # Don't mutate the input args
            vllm_serve_args = vllm_serve_args + [
                "--port", str(get_open_port())
            ]
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        parser = FlexibleArgumentParser(
            description="vLLM's remote OpenAI server.")
        parser = make_arg_parser(parser)
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        args = parser.parse_args(["--model", model, *vllm_serve_args])
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        self.host = str(args.host or 'localhost')
        self.port = int(args.port)

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        # download the model before starting the server to avoid timeout
        is_local = os.path.isdir(model)
        if not is_local:
            engine_args = AsyncEngineArgs.from_cli_args(args)
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            model_config = engine_args.create_model_config()
            load_config = engine_args.create_load_config()

            model_loader = get_model_loader(load_config)
            model_loader.download_model(model_config)
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        env = os.environ.copy()
        # the current process might initialize cuda,
        # to be safe, we should use spawn method
        env['VLLM_WORKER_MULTIPROC_METHOD'] = 'spawn'
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        if env_dict is not None:
            env.update(env_dict)
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        self.proc = subprocess.Popen(
            ["vllm", "serve", model, *vllm_serve_args],
            env=env,
            stdout=sys.stdout,
            stderr=sys.stderr,
        )
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        max_wait_seconds = max_wait_seconds or 240
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        self._wait_for_server(url=self.url_for("health"),
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                              timeout=max_wait_seconds)
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    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_value, traceback):
        self.proc.terminate()
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        try:
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            self.proc.wait(8)
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        except subprocess.TimeoutExpired:
            # force kill if needed
            self.proc.kill()
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    def _wait_for_server(self, *, url: str, timeout: float):
        # run health check
        start = time.time()
        while True:
            try:
                if requests.get(url).status_code == 200:
                    break
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            except Exception:
                # this exception can only be raised by requests.get,
                # which means the server is not ready yet.
                # the stack trace is not useful, so we suppress it
                # by using `raise from None`.
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                result = self.proc.poll()
                if result is not None and result != 0:
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                    raise RuntimeError("Server exited unexpectedly.") from None
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                time.sleep(0.5)
                if time.time() - start > timeout:
                    raise RuntimeError(
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                        "Server failed to start in time.") from None
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    @property
    def url_root(self) -> str:
        return f"http://{self.host}:{self.port}"

    def url_for(self, *parts: str) -> str:
        return self.url_root + "/" + "/".join(parts)

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    def get_client(self, **kwargs):
        if "timeout" not in kwargs:
            kwargs["timeout"] = 600
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        return openai.OpenAI(
            base_url=self.url_for("v1"),
            api_key=self.DUMMY_API_KEY,
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            max_retries=0,
            **kwargs,
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        )

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    def get_async_client(self, **kwargs):
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        if "timeout" not in kwargs:
            kwargs["timeout"] = 600
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        return openai.AsyncOpenAI(base_url=self.url_for("v1"),
                                  api_key=self.DUMMY_API_KEY,
                                  max_retries=0,
                                  **kwargs)
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def _test_completion(
    client: openai.OpenAI,
    model: str,
    prompt: str,
    token_ids: List[int],
):
    results = []

    # test with text prompt
    completion = client.completions.create(model=model,
                                           prompt=prompt,
                                           max_tokens=5,
                                           temperature=0.0)

    results.append({
        "test": "single_completion",
        "text": completion.choices[0].text,
        "finish_reason": completion.choices[0].finish_reason,
        "usage": completion.usage,
    })

    # test using token IDs
    completion = client.completions.create(
        model=model,
        prompt=token_ids,
        max_tokens=5,
        temperature=0.0,
    )

    results.append({
        "test": "token_ids",
        "text": completion.choices[0].text,
        "finish_reason": completion.choices[0].finish_reason,
        "usage": completion.usage,
    })

    # test seeded random sampling
    completion = client.completions.create(model=model,
                                           prompt=prompt,
                                           max_tokens=5,
                                           seed=33,
                                           temperature=1.0)

    results.append({
        "test": "seeded_sampling",
        "text": completion.choices[0].text,
        "finish_reason": completion.choices[0].finish_reason,
        "usage": completion.usage,
    })

    # test seeded random sampling with multiple prompts
    completion = client.completions.create(model=model,
                                           prompt=[prompt, prompt],
                                           max_tokens=5,
                                           seed=33,
                                           temperature=1.0)

    results.append({
        "test":
        "seeded_sampling",
        "text": [choice.text for choice in completion.choices],
        "finish_reason":
        [choice.finish_reason for choice in completion.choices],
        "usage":
        completion.usage,
    })

    # test simple list
    batch = client.completions.create(
        model=model,
        prompt=[prompt, prompt],
        max_tokens=5,
        temperature=0.0,
    )

    results.append({
        "test": "simple_list",
        "text0": batch.choices[0].text,
        "text1": batch.choices[1].text,
    })

    # test streaming
    batch = client.completions.create(
        model=model,
        prompt=[prompt, prompt],
        max_tokens=5,
        temperature=0.0,
        stream=True,
    )

    texts = [""] * 2
    for chunk in batch:
        assert len(chunk.choices) == 1
        choice = chunk.choices[0]
        texts[choice.index] += choice.text

    results.append({
        "test": "streaming",
        "texts": texts,
    })

    return results


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def _test_completion_close(
    client: openai.OpenAI,
    model: str,
    prompt: str,
):
    results = []

    # test with text prompt
    completion = client.completions.create(model=model,
                                           prompt=prompt,
                                           max_tokens=1,
                                           logprobs=5,
                                           temperature=0.0)

    logporbs = completion.choices[0].logprobs.top_logprobs[0]
    logporbs = {k: round(v, 2) for k, v in logporbs.items()}

    results.append({
        "test": "completion_close",
        "logprobs": logporbs,
    })

    return results


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def _test_embeddings(
    client: openai.OpenAI,
    model: str,
    text: str,
):
    results = []

    # test with text input
    embeddings = client.embeddings.create(
        model=model,
        input=text,
        encoding_format="float",
    )

    results.append({
        "test": "single_embedding",
        "embedding": embeddings.data[0].embedding,
        "usage": embeddings.usage,
    })

    return results


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def _test_image_text(
    client: openai.OpenAI,
    model_name: str,
    image_url: str,
):
    results = []

    # test pure text input
    messages = [{
        "role":
        "user",
        "content": [
            {
                "type": "text",
                "text": "How do you feel today?"
            },
        ],
    }]

    chat_completion = client.chat.completions.create(model=model_name,
                                                     messages=messages,
                                                     temperature=0.0,
                                                     max_tokens=1,
                                                     logprobs=True,
                                                     top_logprobs=5)
    top_logprobs = chat_completion.choices[0].logprobs.content[0].top_logprobs

    for x in top_logprobs:
        x.logprob = round(x.logprob, 2)

    results.append({
        "test": "pure_text",
        "logprobs": top_logprobs,
    })

    messages = [{
        "role":
        "user",
        "content": [
            {
                "type": "image_url",
                "image_url": {
                    "url": image_url
                }
            },
            {
                "type": "text",
                "text": "What's in this image?"
            },
        ],
    }]

    chat_completion = client.chat.completions.create(model=model_name,
                                                     messages=messages,
                                                     temperature=0.0,
                                                     max_tokens=1,
                                                     logprobs=True,
                                                     top_logprobs=5)
    top_logprobs = chat_completion.choices[0].logprobs.content[0].top_logprobs

    results.append({
        "test": "text_image",
        "logprobs": top_logprobs,
    })

    return results
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def compare_two_settings(model: str,
                         arg1: List[str],
                         arg2: List[str],
                         env1: Optional[Dict[str, str]] = None,
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                         env2: Optional[Dict[str, str]] = None,
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                         *,
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                         method: str = "generate",
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                         max_wait_seconds: Optional[float] = None) -> None:
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    """
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    Launch API server with two different sets of arguments/environments
    and compare the results of the API calls.

    Args:
        model: The model to test.
        arg1: The first set of arguments to pass to the API server.
        arg2: The second set of arguments to pass to the API server.
        env1: The first set of environment variables to pass to the API server.
        env2: The second set of environment variables to pass to the API server.
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    """

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    compare_all_settings(
        model,
        [arg1, arg2],
        [env1, env2],
        method=method,
        max_wait_seconds=max_wait_seconds,
    )


def compare_all_settings(model: str,
                         all_args: List[List[str]],
                         all_envs: List[Optional[Dict[str, str]]],
                         *,
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                         method: str = "generate",
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                         max_wait_seconds: Optional[float] = None) -> None:
    """
    Launch API server with several different sets of arguments/environments
    and compare the results of the API calls with the first set of arguments.
    Args:
        model: The model to test.
        all_args: A list of argument lists to pass to the API server.
        all_envs: A list of environment dictionaries to pass to the API server.
    """

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    trust_remote_code = False
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    for args in all_args:
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        if "--trust-remote-code" in args:
            trust_remote_code = True
            break

    tokenizer_mode = "auto"
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    for args in all_args:
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        if "--tokenizer-mode" in args:
            tokenizer_mode = args[args.index("--tokenizer-mode") + 1]
            break

    tokenizer = get_tokenizer(
        model,
        trust_remote_code=trust_remote_code,
        tokenizer_mode=tokenizer_mode,
    )
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    can_force_load_format = True

    for args in all_args:
        if "--load-format" in args:
            can_force_load_format = False
            break
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    prompt = "Hello, my name is"
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    token_ids = tokenizer(prompt).input_ids
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    ref_results: List = []
    for i, (args, env) in enumerate(zip(all_args, all_envs)):
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        if can_force_load_format:
            # we are comparing the results and
            # usually we don't need real weights.
            # we force to use dummy weights by default,
            # and it should work for most of the cases.
            # if not, we can use VLLM_TEST_FORCE_LOAD_FORMAT
            # environment variable to force the load format,
            # e.g. in quantization tests.
            args = args + ["--load-format", envs.VLLM_TEST_FORCE_LOAD_FORMAT]
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        compare_results: List = []
        results = ref_results if i == 0 else compare_results
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        with RemoteOpenAIServer(model,
                                args,
                                env_dict=env,
                                max_wait_seconds=max_wait_seconds) as server:
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            client = server.get_client()

            # test models list
            models = client.models.list()
            models = models.data
            served_model = models[0]
            results.append({
                "test": "models_list",
                "id": served_model.id,
                "root": served_model.root,
            })

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            if method == "generate":
                results += _test_completion(client, model, prompt, token_ids)
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            elif method == "generate_close":
                results += _test_completion_close(client, model, prompt)
            elif method == "generate_with_image":
                results += _test_image_text(
                    client, model,
                    "https://upload.wikimedia.org/wikipedia/commons/0/0b/RGBA_comp.png"
                )
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            elif method == "encode":
                results += _test_embeddings(client, model, prompt)
            else:
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                raise ValueError(f"Unknown method: {method}")
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            if i > 0:
                # if any setting fails, raise an error early
                ref_args = all_args[0]
                ref_envs = all_envs[0]
                compare_args = all_args[i]
                compare_envs = all_envs[i]
                for ref_result, compare_result in zip(ref_results,
                                                      compare_results):
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                    ref_result = copy.deepcopy(ref_result)
                    compare_result = copy.deepcopy(compare_result)
                    if "embedding" in ref_result and method == "encode":
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                        sim = F.cosine_similarity(
                            torch.tensor(ref_result["embedding"]),
                            torch.tensor(compare_result["embedding"]),
                            dim=0,
                        )
                        assert sim >= 0.999, (
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                            f"Embedding for {model=} are not the same.\n"
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                            f"cosine_similarity={sim}\n")
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                        del ref_result["embedding"]
                        del compare_result["embedding"]
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                    assert ref_result == compare_result, (
                        f"Results for {model=} are not the same.\n"
                        f"{ref_args=} {ref_envs=}\n"
                        f"{compare_args=} {compare_envs=}\n"
                        f"{ref_result=}\n"
                        f"{compare_result=}\n")
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def init_test_distributed_environment(
    tp_size: int,
    pp_size: int,
    rank: int,
    distributed_init_port: str,
    local_rank: int = -1,
) -> None:
    distributed_init_method = f"tcp://localhost:{distributed_init_port}"
    init_distributed_environment(
        world_size=pp_size * tp_size,
        rank=rank,
        distributed_init_method=distributed_init_method,
        local_rank=local_rank)
    ensure_model_parallel_initialized(tp_size, pp_size)


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def multi_process_parallel(
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    tp_size: int,
    pp_size: int,
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    test_target: Any,
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) -> None:
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    import ray

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    # Using ray helps debugging the error when it failed
    # as compared to multiprocessing.
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    # NOTE: We need to set working_dir for distributed tests,
    # otherwise we may get import errors on ray workers
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    ray.init(num_gpus=tp_size, runtime_env={"working_dir": VLLM_PATH})
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    distributed_init_port = get_open_port()
    refs = []
    for rank in range(tp_size * pp_size):
        refs.append(
            test_target.remote(tp_size, pp_size, rank, distributed_init_port))
    ray.get(refs)

    ray.shutdown()
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@contextmanager
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def error_on_warning(category: Type[Warning] = Warning):
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    """
    Within the scope of this context manager, tests will fail if any warning
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    of the given category is emitted.
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    """
    with warnings.catch_warnings():
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        warnings.filterwarnings("error", category=category)
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        yield
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def get_physical_device_indices(devices):
    visible_devices = os.environ.get("CUDA_VISIBLE_DEVICES")
    if visible_devices is None:
        return devices

    visible_indices = [int(x) for x in visible_devices.split(",")]
    index_mapping = {i: physical for i, physical in enumerate(visible_indices)}
    return [index_mapping[i] for i in devices if i in index_mapping]


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@_nvml()
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def wait_for_gpu_memory_to_clear(devices: List[int],
                                 threshold_bytes: int,
                                 timeout_s: float = 120) -> None:
    # Use nvml instead of pytorch to reduce measurement error from torch cuda
    # context.
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    devices = get_physical_device_indices(devices)
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    start_time = time.time()
    while True:
        output: Dict[int, str] = {}
        output_raw: Dict[int, float] = {}
        for device in devices:
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            if current_platform.is_rocm():
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                dev_handle = amdsmi_get_processor_handles()[device]
                mem_info = amdsmi_get_gpu_vram_usage(dev_handle)
                gb_used = mem_info["vram_used"] / 2**10
            else:
                dev_handle = nvmlDeviceGetHandleByIndex(device)
                mem_info = nvmlDeviceGetMemoryInfo(dev_handle)
                gb_used = mem_info.used / 2**30
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            output_raw[device] = gb_used
            output[device] = f'{gb_used:.02f}'

        print('gpu memory used (GB): ', end='')
        for k, v in output.items():
            print(f'{k}={v}; ', end='')
        print('')

        dur_s = time.time() - start_time
        if all(v <= (threshold_bytes / 2**30) for v in output_raw.values()):
            print(f'Done waiting for free GPU memory on devices {devices=} '
                  f'({threshold_bytes/2**30=}) {dur_s=:.02f}')
            break

        if dur_s >= timeout_s:
            raise ValueError(f'Memory of devices {devices=} not free after '
                             f'{dur_s=:.02f} ({threshold_bytes/2**30=})')

        time.sleep(5)
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_P = ParamSpec("_P")


def fork_new_process_for_each_test(
        f: Callable[_P, None]) -> Callable[_P, None]:
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    """Decorator to fork a new process for each test function.
    See https://github.com/vllm-project/vllm/issues/7053 for more details.
    """
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    @functools.wraps(f)
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    def wrapper(*args: _P.args, **kwargs: _P.kwargs) -> None:
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        # Make the process the leader of its own process group
        # to avoid sending SIGTERM to the parent process
        os.setpgrp()
        from _pytest.outcomes import Skipped
        pid = os.fork()
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        print(f"Fork a new process to run a test {pid}")
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        if pid == 0:
            try:
                f(*args, **kwargs)
            except Skipped as e:
                # convert Skipped to exit code 0
                print(str(e))
                os._exit(0)
            except Exception:
                import traceback
                traceback.print_exc()
                os._exit(1)
            else:
                os._exit(0)
        else:
            pgid = os.getpgid(pid)
            _pid, _exitcode = os.waitpid(pid, 0)
            # ignore SIGTERM signal itself
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            old_signal_handler = signal.signal(signal.SIGTERM, signal.SIG_IGN)
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            # kill all child processes
            os.killpg(pgid, signal.SIGTERM)
            # restore the signal handler
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            signal.signal(signal.SIGTERM, old_signal_handler)
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            assert _exitcode == 0, (f"function {f} failed when called with"
                                    f" args {args} and kwargs {kwargs}")

    return wrapper
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zhuwenwen committed
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def large_gpu_test(*, min_gb: int):
    """
    Decorate a test to be skipped if no GPU is available or it does not have
    sufficient memory.

    Currently, the CI machine uses L4 GPU which has 24 GB VRAM.
    """
    try:
        if current_platform.is_cpu():
            memory_gb = 0
        else:
            memory_gb = current_platform.get_device_total_memory() / GB_bytes
    except Exception as e:
        warnings.warn(
            f"An error occurred when finding the available memory: {e}",
            stacklevel=2,
        )

        memory_gb = 0

    test_skipif = pytest.mark.skipif(
        memory_gb < min_gb,
        reason=f"Need at least {memory_gb}GB GPU memory to run the test.",
    )

    def wrapper(f: Callable[_P, None]) -> Callable[_P, None]:
        return test_skipif(fork_new_process_for_each_test(f))

    return wrapper

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def large_gpu_mark(min_gb: int) -> pytest.MarkDecorator:
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    """
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    Get a pytest mark, which skips the test if the GPU doesn't meet
    a minimum memory requirement in GB.
    
    This can be leveraged via `@large_gpu_test` to skip tests in environments
    without enough resources, or called when filtering tests to run directly.
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    """
    try:
        if current_platform.is_cpu():
            memory_gb = 0
        else:
            memory_gb = current_platform.get_device_total_memory() / GB_bytes
    except Exception as e:
        warnings.warn(
            f"An error occurred when finding the available memory: {e}",
            stacklevel=2,
        )
        memory_gb = 0

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    return pytest.mark.skipif(
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        memory_gb < min_gb,
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        reason=f"Need at least {min_gb}GB GPU memory to run the test.",
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    )

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def large_gpu_test(*, min_gb: int):
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    """
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    Decorate a test to be skipped if no GPU is available or it does not have
    sufficient memory.

    Currently, the CI machine uses L4 GPU which has 24 GB VRAM.
    """
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    mark = large_gpu_mark(min_gb)
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    def wrapper(f: Callable[_P, None]) -> Callable[_P, None]:
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        return mark(f)
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    return wrapper


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def multi_gpu_marks(*, num_gpus: int):
    """Get a collection of pytest marks to apply for `@multi_gpu_test`."""
    test_selector = pytest.mark.distributed(num_gpus=num_gpus)
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    test_skipif = pytest.mark.skipif(
        cuda_device_count_stateless() < num_gpus,
        reason=f"Need at least {num_gpus} GPUs to run the test.",
    )

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    return [test_selector, test_skipif]


def multi_gpu_test(*, num_gpus: int):
    """
    Decorate a test to be run only when multiple GPUs are available.
    """
    marks = multi_gpu_marks(num_gpus=num_gpus)

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    def wrapper(f: Callable[_P, None]) -> Callable[_P, None]:
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        func = fork_new_process_for_each_test(f)
        for mark in reversed(marks):
            func = mark(func)

        return func
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    return wrapper


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async def completions_with_server_args(
    prompts: List[str],
    model_name: str,
    server_cli_args: List[str],
    num_logprobs: Optional[int],
    max_wait_seconds: int = 240,
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    max_tokens: Union[int, list] = 5,
) -> List[Completion]:
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    '''Construct a remote OpenAI server, obtain an async client to the
    server & invoke the completions API to obtain completions.

    Args:
      prompts: test prompts
      model_name: model to spin up on the vLLM server
      server_cli_args: CLI args for starting the server
      num_logprobs: Number of logprobs to report (or `None`)
      max_wait_seconds: timeout interval for bringing up server.
                        Default: 240sec
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      max_tokens: max_tokens value for each of the given input prompts.
        if only one max_token value is given, the same value is used
        for all the prompts.
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    Returns:
      OpenAI Completion instance
    '''

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    if isinstance(max_tokens, int):
        max_tokens = [max_tokens] * len(prompts)

    assert len(max_tokens) == len(prompts)

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    outputs = None
    with RemoteOpenAIServer(model_name,
                            server_cli_args,
                            max_wait_seconds=max_wait_seconds) as server:
        client = server.get_async_client()
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        outputs = [ client.completions.create(model=model_name,
                                              prompt=[p],
                                              temperature=0,
                                              stream=False,
                                              max_tokens=max_tok,
                                              logprobs=num_logprobs) \
                    for p, max_tok in zip(prompts, max_tokens) ]
        outputs = await asyncio.gather(*outputs)

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    assert outputs is not None, "Completion API call failed."
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    return outputs


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def get_client_text_generations(completions: List[Completion]) -> List[str]:
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    '''Extract generated tokens from the output of a
    request made to an Open-AI-protocol completions endpoint.
    '''
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    assert all([len(x.choices) == 1 for x in completions])
    return [x.choices[0].text for x in completions]
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def get_client_text_logprob_generations(
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        completions: List[Completion]) -> List[TextTextLogprobs]:
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    '''Operates on the output of a request made to an Open-AI-protocol
    completions endpoint; obtains top-rank logprobs for each token in
    each :class:`SequenceGroup`
    '''
    text_generations = get_client_text_generations(completions)
    text = ''.join(text_generations)
    return [(text_generations, text,
             (None if x.logprobs is None else x.logprobs.top_logprobs))
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            for completion in completions for x in completion.choices]