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vllm.benchmarks.serve

Benchmark online serving throughput.

On the server side, run one of the following commands to launch the vLLM OpenAI API server: vllm serve

On the client side, run: vllm bench serve \ --backend \ --label \ --model \ --dataset-name \ --request-rate \ --num-prompts

MILLISECONDS_TO_SECONDS_CONVERSION module-attribute

MILLISECONDS_TO_SECONDS_CONVERSION = 1000

TERM_PLOTLIB_AVAILABLE module-attribute

TERM_PLOTLIB_AVAILABLE = (
    find_spec("termplotlib") is not None
    and which("gnuplot") is not None
)

BenchmarkMetrics dataclass

Source code in vllm/benchmarks/serve.py
@dataclass
class BenchmarkMetrics:
    completed: int
    total_input: int
    total_output: int
    request_throughput: float
    request_goodput: float
    output_throughput: float
    total_token_throughput: float
    mean_ttft_ms: float
    median_ttft_ms: float
    std_ttft_ms: float
    percentiles_ttft_ms: list[tuple[float, float]]
    mean_tpot_ms: float
    median_tpot_ms: float
    std_tpot_ms: float
    percentiles_tpot_ms: list[tuple[float, float]]
    mean_itl_ms: float
    median_itl_ms: float
    std_itl_ms: float
    percentiles_itl_ms: list[tuple[float, float]]
    # E2EL stands for end-to-end latency per request.
    # It is the time taken on the client side from sending
    # a request to receiving a complete response.
    mean_e2el_ms: float
    median_e2el_ms: float
    std_e2el_ms: float
    percentiles_e2el_ms: list[tuple[float, float]]
    # Max output tokens per second and concurrent requests at that peak
    max_output_tokens_per_s: float
    max_concurrent_requests: int

completed instance-attribute

completed: int

max_concurrent_requests instance-attribute

max_concurrent_requests: int

max_output_tokens_per_s instance-attribute

max_output_tokens_per_s: float

mean_e2el_ms instance-attribute

mean_e2el_ms: float

mean_itl_ms instance-attribute

mean_itl_ms: float

mean_tpot_ms instance-attribute

mean_tpot_ms: float

mean_ttft_ms instance-attribute

mean_ttft_ms: float

median_e2el_ms instance-attribute

median_e2el_ms: float

median_itl_ms instance-attribute

median_itl_ms: float

median_tpot_ms instance-attribute

median_tpot_ms: float

median_ttft_ms instance-attribute

median_ttft_ms: float

output_throughput instance-attribute

output_throughput: float

percentiles_e2el_ms instance-attribute

percentiles_e2el_ms: list[tuple[float, float]]

percentiles_itl_ms instance-attribute

percentiles_itl_ms: list[tuple[float, float]]

percentiles_tpot_ms instance-attribute

percentiles_tpot_ms: list[tuple[float, float]]

percentiles_ttft_ms instance-attribute

percentiles_ttft_ms: list[tuple[float, float]]

request_goodput instance-attribute

request_goodput: float

request_throughput instance-attribute

request_throughput: float

std_e2el_ms instance-attribute

std_e2el_ms: float

std_itl_ms instance-attribute

std_itl_ms: float

std_tpot_ms instance-attribute

std_tpot_ms: float

std_ttft_ms instance-attribute

std_ttft_ms: float

total_input instance-attribute

total_input: int

total_output instance-attribute

total_output: int

total_token_throughput instance-attribute

total_token_throughput: float

__init__

__init__(
    completed: int,
    total_input: int,
    total_output: int,
    request_throughput: float,
    request_goodput: float,
    output_throughput: float,
    total_token_throughput: float,
    mean_ttft_ms: float,
    median_ttft_ms: float,
    std_ttft_ms: float,
    percentiles_ttft_ms: list[tuple[float, float]],
    mean_tpot_ms: float,
    median_tpot_ms: float,
    std_tpot_ms: float,
    percentiles_tpot_ms: list[tuple[float, float]],
    mean_itl_ms: float,
    median_itl_ms: float,
    std_itl_ms: float,
    percentiles_itl_ms: list[tuple[float, float]],
    mean_e2el_ms: float,
    median_e2el_ms: float,
    std_e2el_ms: float,
    percentiles_e2el_ms: list[tuple[float, float]],
    max_output_tokens_per_s: float,
    max_concurrent_requests: int,
) -> None

EmbedBenchmarkMetrics dataclass

Source code in vllm/benchmarks/serve.py
@dataclass
class EmbedBenchmarkMetrics:
    completed: int
    total_input: int
    request_throughput: float
    total_token_throughput: float
    mean_e2el_ms: float
    std_e2el_ms: float
    median_e2el_ms: float
    percentiles_e2el_ms: float

completed instance-attribute

completed: int

mean_e2el_ms instance-attribute

mean_e2el_ms: float

median_e2el_ms instance-attribute

median_e2el_ms: float

percentiles_e2el_ms instance-attribute

percentiles_e2el_ms: float

request_throughput instance-attribute

request_throughput: float

std_e2el_ms instance-attribute

std_e2el_ms: float

total_input instance-attribute

total_input: int

total_token_throughput instance-attribute

total_token_throughput: float

__init__

__init__(
    completed: int,
    total_input: int,
    request_throughput: float,
    total_token_throughput: float,
    mean_e2el_ms: float,
    std_e2el_ms: float,
    median_e2el_ms: float,
    percentiles_e2el_ms: float,
) -> None

TaskType

Bases: Enum

Source code in vllm/benchmarks/serve.py
class TaskType(Enum):
    GENERATION = "generation"
    EMBEDDING = "embedding"

EMBEDDING class-attribute instance-attribute

EMBEDDING = 'embedding'

GENERATION class-attribute instance-attribute

GENERATION = 'generation'

_get_current_request_rate

_get_current_request_rate(
    ramp_up_strategy: Optional[
        Literal["linear", "exponential"]
    ],
    ramp_up_start_rps: Optional[int],
    ramp_up_end_rps: Optional[int],
    request_index: int,
    total_requests: int,
    request_rate: float,
) -> float
Source code in vllm/benchmarks/serve.py
def _get_current_request_rate(
    ramp_up_strategy: Optional[Literal["linear", "exponential"]],
    ramp_up_start_rps: Optional[int],
    ramp_up_end_rps: Optional[int],
    request_index: int,
    total_requests: int,
    request_rate: float,
) -> float:
    if (
        ramp_up_strategy
        and ramp_up_start_rps is not None
        and ramp_up_end_rps is not None
    ):
        progress = request_index / max(total_requests - 1, 1)
        if ramp_up_strategy == "linear":
            increase = (ramp_up_end_rps - ramp_up_start_rps) * progress
            return ramp_up_start_rps + increase
        elif ramp_up_strategy == "exponential":
            ratio = ramp_up_end_rps / ramp_up_start_rps
            return ramp_up_start_rps * (ratio**progress)
        else:
            raise ValueError(f"Unknown ramp-up strategy: {ramp_up_strategy}")
    return request_rate

add_cli_args

add_cli_args(parser: ArgumentParser)
Source code in vllm/benchmarks/serve.py
def add_cli_args(parser: argparse.ArgumentParser):
    add_dataset_parser(parser)
    parser.add_argument(
        "--label",
        type=str,
        default=None,
        help="The label (prefix) of the benchmark results. If not specified, "
        "the value of '--backend' will be used as the label.",
    )
    parser.add_argument(
        "--backend",
        type=str,
        default="openai",
        choices=list(ASYNC_REQUEST_FUNCS.keys()),
        help="The type of backend or endpoint to use for the benchmark.",
    )
    parser.add_argument(
        "--base-url",
        type=str,
        default=None,
        help="Server or API base url if not using http host and port.",
    )
    # Use 127.0.0.1 here instead of localhost to force the use of ipv4
    parser.add_argument("--host", type=str, default="127.0.0.1")
    parser.add_argument("--port", type=int, default=8000)
    parser.add_argument(
        "--endpoint",
        type=str,
        default="/v1/completions",
        help="API endpoint.",
    )
    parser.add_argument(
        "--header",
        metavar="KEY=VALUE",
        nargs="*",
        help="Key-value pairs (e.g, --header x-additional-info=0.3.3) "
        "for headers to be passed with each request. These headers override "
        "per backend constants and values set via environment variable, and "
        "will be overriden by other arguments (such as request ids).",
    )
    parser.add_argument(
        "--max-concurrency",
        type=int,
        default=None,
        help="Maximum number of concurrent requests. This can be used "
        "to help simulate an environment where a higher level component "
        "is enforcing a maximum number of concurrent requests. While the "
        "--request-rate argument controls the rate at which requests are "
        "initiated, this argument will control how many are actually allowed "
        "to execute at a time. This means that when used in combination, the "
        "actual request rate may be lower than specified with --request-rate, "
        "if the server is not processing requests fast enough to keep up.",
    )

    parser.add_argument(
        "--model",
        type=str,
        required=True,
        help="Name of the model.",
    )
    parser.add_argument(
        "--tokenizer",
        type=str,
        help="Name or path of the tokenizer, if not using the default tokenizer.",  # noqa: E501
    )
    parser.add_argument("--use-beam-search", action="store_true")
    parser.add_argument(
        "--logprobs",
        type=int,
        default=None,
        help=(
            "Number of logprobs-per-token to compute & return as part of "
            "the request. If unspecified, then either (1) if beam search "
            "is disabled, no logprobs are computed & a single dummy "
            "logprob is returned for each token; or (2) if beam search "
            "is enabled 1 logprob per token is computed"
        ),
    )
    parser.add_argument(
        "--request-rate",
        type=float,
        default=float("inf"),
        help="Number of requests per second. If this is inf, "
        "then all the requests are sent at time 0. "
        "Otherwise, we use Poisson process or gamma distribution "
        "to synthesize the request arrival times.",
    )
    parser.add_argument(
        "--burstiness",
        type=float,
        default=1.0,
        help="Burstiness factor of the request generation. "
        "Only take effect when request_rate is not inf. "
        "Default value is 1, which follows Poisson process. "
        "Otherwise, the request intervals follow a gamma distribution. "
        "A lower burstiness value (0 < burstiness < 1) results in more "
        "bursty requests. A higher burstiness value (burstiness > 1) "
        "results in a more uniform arrival of requests.",
    )
    parser.add_argument(
        "--trust-remote-code",
        action="store_true",
        help="Trust remote code from huggingface",
    )
    parser.add_argument(
        "--disable-tqdm",
        action="store_true",
        help="Specify to disable tqdm progress bar.",
    )
    parser.add_argument(
        "--profile",
        action="store_true",
        help="Use Torch Profiler. The endpoint must be launched with "
        "VLLM_TORCH_PROFILER_DIR to enable profiler.",
    )
    parser.add_argument(
        "--save-result",
        action="store_true",
        help="Specify to save benchmark results to a json file",
    )
    parser.add_argument(
        "--save-detailed",
        action="store_true",
        help="When saving the results, whether to include per request "
        "information such as response, error, ttfs, tpots, etc.",
    )
    parser.add_argument(
        "--append-result",
        action="store_true",
        help="Append the benchmark result to the existing json file.",
    )
    parser.add_argument(
        "--metadata",
        metavar="KEY=VALUE",
        nargs="*",
        help="Key-value pairs (e.g, --metadata version=0.3.3 tp=1) "
        "for metadata of this run to be saved in the result JSON file "
        "for record keeping purposes.",
    )
    parser.add_argument(
        "--result-dir",
        type=str,
        default=None,
        help="Specify directory to save benchmark json results."
        "If not specified, results are saved in the current directory.",
    )
    parser.add_argument(
        "--result-filename",
        type=str,
        default=None,
        help="Specify the filename to save benchmark json results."
        "If not specified, results will be saved in "
        "{label}-{args.request_rate}qps-{base_model_id}-{current_dt}.json"  # noqa
        " format.",
    )
    parser.add_argument(
        "--ignore-eos",
        action="store_true",
        help="Set ignore_eos flag when sending the benchmark request."
        "Warning: ignore_eos is not supported in deepspeed_mii and tgi.",
    )
    parser.add_argument(
        "--percentile-metrics",
        type=str,
        default="ttft,tpot,itl",
        help="Comma-separated list of selected metrics to report percentils. "
        "This argument specifies the metrics to report percentiles. "
        'Allowed metric names are "ttft", "tpot", "itl", "e2el". ',
    )
    parser.add_argument(
        "--metric-percentiles",
        type=str,
        default="99",
        help="Comma-separated list of percentiles for selected metrics. "
        'To report 25-th, 50-th, and 75-th percentiles, use "25,50,75". '
        'Default value is "99".'
        'Use "--percentile-metrics" to select metrics.',
    )
    parser.add_argument(
        "--goodput",
        nargs="+",
        required=False,
        help='Specify service level objectives for goodput as "KEY:VALUE" '
        "pairs, where the key is a metric name, and the value is in "
        'milliseconds. Multiple "KEY:VALUE" pairs can be provided, '
        "separated by spaces. Allowed request level metric names are "
        '"ttft", "tpot", "e2el". For more context on the definition of '
        "goodput, refer to DistServe paper: https://arxiv.org/pdf/2401.09670 "
        "and the blog: https://hao-ai-lab.github.io/blogs/distserve",
    )
    parser.add_argument(
        "--request-id-prefix",
        type=str,
        required=False,
        default="benchmark-serving",
        help="Specify the prefix of request id.",
    )

    sampling_group = parser.add_argument_group("sampling parameters")
    sampling_group.add_argument(
        "--top-p",
        type=float,
        default=None,
        help="Top-p sampling parameter. Only has effect on openai-compatible backends.",
    )
    sampling_group.add_argument(
        "--top-k",
        type=int,
        default=None,
        help="Top-k sampling parameter. Only has effect on openai-compatible backends.",
    )
    sampling_group.add_argument(
        "--min-p",
        type=float,
        default=None,
        help="Min-p sampling parameter. Only has effect on openai-compatible backends.",
    )
    sampling_group.add_argument(
        "--temperature",
        type=float,
        default=None,
        help="Temperature sampling parameter. Only has effect on "
        "openai-compatible backends. If not specified, default to greedy "
        "decoding (i.e. temperature==0.0).",
    )
    sampling_group.add_argument(
        "--frequency-penalty",
        type=float,
        default=None,
        help="Frequency penalty sampling parameter. Only has effect on "
        "openai-compatible backends.",
    )
    sampling_group.add_argument(
        "--presence-penalty",
        type=float,
        default=None,
        help="Presence penalty sampling parameter. Only has effect on "
        "openai-compatible backends.",
    )
    sampling_group.add_argument(
        "--repetition-penalty",
        type=float,
        default=None,
        help="Repetition penalty sampling parameter. Only has effect on "
        "openai-compatible backends.",
    )

    parser.add_argument(
        "--tokenizer-mode",
        type=str,
        default="auto",
        choices=["auto", "slow", "mistral", "custom"],
        help='The tokenizer mode.\n\n* "auto" will use the '
        'fast tokenizer if available.\n* "slow" will '
        "always use the slow tokenizer. \n* "
        '"mistral" will always use the `mistral_common` tokenizer. \n*'
        '"custom" will use --tokenizer to select the preregistered tokenizer.',
    )

    parser.add_argument(
        "--served-model-name",
        type=str,
        default=None,
        help="The model name used in the API. "
        "If not specified, the model name will be the "
        "same as the ``--model`` argument. ",
    )

    parser.add_argument(
        "--lora-modules",
        nargs="+",
        default=None,
        help="A subset of LoRA module names passed in when "
        "launching the server. For each request, the "
        "script chooses a LoRA module at random.",
    )

    parser.add_argument(
        "--ramp-up-strategy",
        type=str,
        default=None,
        choices=["linear", "exponential"],
        help="The ramp-up strategy. This would be used to "
        "ramp up the request rate from initial RPS to final "
        "RPS rate (specified by --ramp-up-start-rps and "
        "--ramp-up-end-rps.) over the duration of the benchmark.",
    )
    parser.add_argument(
        "--ramp-up-start-rps",
        type=int,
        default=None,
        help="The starting request rate for ramp-up (RPS). "
        "Needs to be specified when --ramp-up-strategy is used.",
    )
    parser.add_argument(
        "--ramp-up-end-rps",
        type=int,
        default=None,
        help="The ending request rate for ramp-up (RPS). "
        "Needs to be specified when --ramp-up-strategy is used.",
    )
    parser.add_argument(
        "--ready-check-timeout-sec",
        type=int,
        default=600,
        help="Maximum time to wait for the endpoint to become ready "
        "in seconds (default: 600 seconds / 10 minutes). If set to 0, "
        "the ready check will be skipped.",
    )

benchmark async

benchmark(
    task_type: TaskType,
    endpoint_type: str,
    api_url: str,
    base_url: str,
    model_id: str,
    model_name: str,
    tokenizer: PreTrainedTokenizerBase,
    input_requests: list[SampleRequest],
    logprobs: Optional[int],
    request_rate: float,
    burstiness: float,
    disable_tqdm: bool,
    profile: bool,
    selected_percentile_metrics: list[str],
    selected_percentiles: list[float],
    ignore_eos: bool,
    goodput_config_dict: dict[str, float],
    max_concurrency: Optional[int],
    lora_modules: Optional[Iterable[str]],
    extra_headers: Optional[dict],
    extra_body: Optional[dict],
    ramp_up_strategy: Optional[
        Literal["linear", "exponential"]
    ] = None,
    ramp_up_start_rps: Optional[int] = None,
    ramp_up_end_rps: Optional[int] = None,
    ready_check_timeout_sec: int = 600,
)
Source code in vllm/benchmarks/serve.py
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async def benchmark(
    task_type: TaskType,
    endpoint_type: str,
    api_url: str,
    base_url: str,
    model_id: str,
    model_name: str,
    tokenizer: PreTrainedTokenizerBase,
    input_requests: list[SampleRequest],
    logprobs: Optional[int],
    request_rate: float,
    burstiness: float,
    disable_tqdm: bool,
    profile: bool,
    selected_percentile_metrics: list[str],
    selected_percentiles: list[float],
    ignore_eos: bool,
    goodput_config_dict: dict[str, float],
    max_concurrency: Optional[int],
    lora_modules: Optional[Iterable[str]],
    extra_headers: Optional[dict],
    extra_body: Optional[dict],
    ramp_up_strategy: Optional[Literal["linear", "exponential"]] = None,
    ramp_up_start_rps: Optional[int] = None,
    ramp_up_end_rps: Optional[int] = None,
    ready_check_timeout_sec: int = 600,
):
    try:
        request_func = ASYNC_REQUEST_FUNCS[endpoint_type]
    except KeyError:
        raise ValueError(f"Unknown backend: {endpoint_type}") from None

    # Reuses connections across requests to reduce TLS handshake overhead.
    connector = aiohttp.TCPConnector(
        limit=max_concurrency or 0,
        limit_per_host=max_concurrency or 0,
        ttl_dns_cache=300,
        use_dns_cache=True,
        keepalive_timeout=60,
        enable_cleanup_closed=True,
        force_close=False,
        ssl=("https://" in api_url),
    )

    session = aiohttp.ClientSession(
        connector=connector,
        trust_env=True,
        timeout=aiohttp.ClientTimeout(total=6 * 60 * 60),
    )

    print("Starting initial single prompt test run...")
    test_prompt, test_prompt_len, test_output_len, test_mm_content = (
        input_requests[0].prompt,
        input_requests[0].prompt_len,
        input_requests[0].expected_output_len,
        input_requests[0].multi_modal_data,
    )

    assert (
        test_mm_content is None
        or isinstance(test_mm_content, dict)
        or (
            isinstance(test_mm_content, list)
            and all(isinstance(item, dict) for item in test_mm_content)
        )
    ), "multi_modal_data must be a dict or list[dict]"
    test_input = RequestFuncInput(
        model=model_id,
        model_name=model_name,
        prompt=test_prompt,
        api_url=api_url,
        prompt_len=test_prompt_len,
        output_len=test_output_len,
        logprobs=logprobs,
        multi_modal_content=test_mm_content,
        ignore_eos=ignore_eos,
        extra_headers=extra_headers,
        extra_body=extra_body,
    )

    if ready_check_timeout_sec > 0:
        test_output = await wait_for_endpoint(
            request_func,
            test_input,
            session,
            timeout_seconds=ready_check_timeout_sec,
        )
        if not test_output.success:
            raise ValueError(
                "Initial test run failed - Please make sure benchmark "
                "arguments are correctly specified. "
                f"Error: {test_output.error}"
            )
        else:
            print("Initial test run completed. Starting main benchmark run...")
    else:
        print("Skipping endpoint ready check.")

    if lora_modules:
        # For each input request, choose a LoRA module at random.
        lora_modules = iter(
            [random.choice(lora_modules) for _ in range(len(input_requests))]
        )

    if profile:
        print("Starting profiler...")
        profile_input = RequestFuncInput(
            model=model_id,
            model_name=model_name,
            prompt=test_prompt,
            api_url=base_url + "/start_profile",
            prompt_len=test_prompt_len,
            output_len=test_output_len,
            logprobs=logprobs,
            multi_modal_content=test_mm_content,
            ignore_eos=ignore_eos,
            extra_headers=extra_headers,
            extra_body=extra_body,
        )
        profile_output = await request_func(
            request_func_input=profile_input, session=session
        )
        if profile_output.success:
            print("Profiler started")

    distribution = "Poisson process" if burstiness == 1.0 else "Gamma distribution"

    if ramp_up_strategy is not None:
        print(f"Traffic ramp-up strategy: {ramp_up_strategy}.")
        print(
            f"Will increase RPS from {ramp_up_start_rps} to "
            f"{ramp_up_end_rps} RPS over the duration of the benchmark."
        )
    else:
        print(f"Traffic request rate: {request_rate}")

    print(f"Burstiness factor: {burstiness} ({distribution})")
    print(f"Maximum request concurrency: {max_concurrency}")

    pbar = None if disable_tqdm else tqdm(total=len(input_requests))

    # This can be used once the minimum Python version is 3.10 or higher,
    # and it will simplify the code in limited_request_func.
    #    semaphore = (asyncio.Semaphore(max_concurrency)
    #                 if max_concurrency else contextlib.nullcontext())
    semaphore = asyncio.Semaphore(max_concurrency) if max_concurrency else None

    async def limited_request_func(request_func_input, session, pbar):
        if semaphore is None:
            return await request_func(
                request_func_input=request_func_input, session=session, pbar=pbar
            )
        async with semaphore:
            return await request_func(
                request_func_input=request_func_input, session=session, pbar=pbar
            )

    benchmark_start_time = time.perf_counter()
    tasks: list[asyncio.Task] = []

    rps_change_events = []
    last_int_rps = -1
    if ramp_up_strategy is not None and ramp_up_start_rps is not None:
        last_int_rps = ramp_up_start_rps
        rps_change_events.append(
            {
                "rps": last_int_rps,
                "timestamp": datetime.now().isoformat(),
            }
        )

    async for request, current_request_rate in get_request(
        input_requests,
        request_rate,
        burstiness,
        ramp_up_strategy,
        ramp_up_start_rps,
        ramp_up_end_rps,
    ):
        if ramp_up_strategy is not None:
            current_int_rps = int(current_request_rate)
            if current_int_rps > last_int_rps:
                timestamp = datetime.now().isoformat()
                for rps_val in range(last_int_rps + 1, current_int_rps + 1):
                    rps_change_events.append({"rps": rps_val, "timestamp": timestamp})
                last_int_rps = current_int_rps
        prompt, prompt_len, output_len, mm_content, request_id = (
            request.prompt,
            request.prompt_len,
            request.expected_output_len,
            request.multi_modal_data,
            request.request_id,
        )
        req_model_id, req_model_name = model_id, model_name
        if lora_modules:
            req_lora_module = next(lora_modules)
            req_model_id, req_model_name = req_lora_module, req_lora_module

        request_func_input = RequestFuncInput(
            model=req_model_id,
            model_name=req_model_name,
            prompt=prompt,
            api_url=api_url,
            prompt_len=prompt_len,
            output_len=output_len,
            logprobs=logprobs,
            multi_modal_content=mm_content,
            ignore_eos=ignore_eos,
            extra_headers=extra_headers,
            extra_body=extra_body,
            request_id=request_id,
        )
        tasks.append(
            asyncio.create_task(
                limited_request_func(
                    request_func_input=request_func_input, session=session, pbar=pbar
                )
            )
        )
    outputs: list[RequestFuncOutput] = await asyncio.gather(*tasks)

    if pbar is not None:
        pbar.close()

    benchmark_duration = time.perf_counter() - benchmark_start_time

    if task_type == TaskType.GENERATION:
        metrics, actual_output_lens = calculate_metrics(
            input_requests=input_requests,
            outputs=outputs,
            dur_s=benchmark_duration,
            tokenizer=tokenizer,
            selected_percentiles=selected_percentiles,
            goodput_config_dict=goodput_config_dict,
        )
    else:
        metrics = calculate_metrics_for_embeddings(
            outputs=outputs,
            dur_s=benchmark_duration,
            selected_percentiles=selected_percentiles,
        )
        actual_output_lens = 0

    print("{s:{c}^{n}}".format(s=" Serving Benchmark Result ", n=50, c="="))
    print("{:<40} {:<10}".format("Successful requests:", metrics.completed))
    if max_concurrency is not None:
        print("{:<40} {:<10}".format("Maximum request concurrency:", max_concurrency))
    if request_rate != float("inf"):
        print("{:<40} {:<10.2f}".format("Request rate configured (RPS):", request_rate))
    print("{:<40} {:<10.2f}".format("Benchmark duration (s):", benchmark_duration))
    print("{:<40} {:<10}".format("Total input tokens:", metrics.total_input))
    if isinstance(metrics, BenchmarkMetrics):
        print("{:<40} {:<10}".format("Total generated tokens:", metrics.total_output))
    print(
        "{:<40} {:<10.2f}".format(
            "Request throughput (req/s):", metrics.request_throughput
        )
    )
    if goodput_config_dict:
        print(
            "{:<40} {:<10.2f}".format(
                "Request goodput (req/s):", metrics.request_goodput
            )
        )
    if isinstance(metrics, BenchmarkMetrics):
        print(
            "{:<40} {:<10.2f}".format(
                "Output token throughput (tok/s):", metrics.output_throughput
            )
        )
        print(
            "{:<40} {:<10.2f}".format(
                "Peak output token throughput (tok/s):", metrics.max_output_tokens_per_s
            )
        )
        print(
            "{:<40} {:<10.2f}".format(
                "Peak concurrent requests:", metrics.max_concurrent_requests
            )
        )
    print(
        "{:<40} {:<10.2f}".format(
            "Total Token throughput (tok/s):", metrics.total_token_throughput
        )
    )

    if isinstance(metrics, BenchmarkMetrics):
        result = {
            "duration": benchmark_duration,
            "completed": metrics.completed,
            "total_input_tokens": metrics.total_input,
            "total_output_tokens": metrics.total_output,
            "request_throughput": metrics.request_throughput,
            "request_goodput": metrics.request_goodput if goodput_config_dict else None,
            "output_throughput": metrics.output_throughput,
            "total_token_throughput": metrics.total_token_throughput,
            "input_lens": [output.prompt_len for output in outputs],
            "output_lens": actual_output_lens,
            "ttfts": [output.ttft for output in outputs],
            "itls": [output.itl for output in outputs],
            "generated_texts": [output.generated_text for output in outputs],
            "errors": [output.error for output in outputs],
            "max_output_tokens_per_s": metrics.max_output_tokens_per_s,
            "max_concurrent_requests": metrics.max_concurrent_requests,
        }
    else:
        result = {
            "duration": benchmark_duration,
            "completed": metrics.completed,
            "total_input_tokens": metrics.total_input,
            "request_throughput": metrics.request_throughput,
            "total_token_throughput": metrics.total_token_throughput,
            "input_lens": [output.prompt_len for output in outputs],
            "errors": [output.error for output in outputs],
        }

    if rps_change_events:
        result["rps_change_events"] = rps_change_events

    def process_one_metric(
        # E.g., "ttft"
        metric_attribute_name: str,
        # E.g., "TTFT"
        metric_name: str,
        # E.g., "Time to First Token"
        metric_header: str,
    ):
        # This function prints and adds statistics of the specified
        # metric.
        if metric_attribute_name not in selected_percentile_metrics:
            return
        print("{s:{c}^{n}}".format(s=metric_header, n=50, c="-"))
        print(
            "{:<40} {:<10.2f}".format(
                f"Mean {metric_name} (ms):",
                getattr(metrics, f"mean_{metric_attribute_name}_ms"),
            )
        )
        print(
            "{:<40} {:<10.2f}".format(
                f"Median {metric_name} (ms):",
                getattr(metrics, f"median_{metric_attribute_name}_ms"),
            )
        )
        result[f"mean_{metric_attribute_name}_ms"] = getattr(
            metrics, f"mean_{metric_attribute_name}_ms"
        )
        result[f"median_{metric_attribute_name}_ms"] = getattr(
            metrics, f"median_{metric_attribute_name}_ms"
        )
        result[f"std_{metric_attribute_name}_ms"] = getattr(
            metrics, f"std_{metric_attribute_name}_ms"
        )
        for p, value in getattr(metrics, f"percentiles_{metric_attribute_name}_ms"):
            p_word = str(int(p)) if int(p) == p else str(p)
            print("{:<40} {:<10.2f}".format(f"P{p_word} {metric_name} (ms):", value))
            result[f"p{p_word}_{metric_attribute_name}_ms"] = value

    if task_type == TaskType.GENERATION:
        process_one_metric("ttft", "TTFT", "Time to First Token")
        process_one_metric("tpot", "TPOT", "Time per Output Token (excl. 1st token)")
        process_one_metric("itl", "ITL", "Inter-token Latency")
    process_one_metric("e2el", "E2EL", "End-to-end Latency")

    print("=" * 50)

    if profile:
        print("Stopping profiler...")
        profile_input = RequestFuncInput(
            model=model_id,
            prompt=test_prompt,
            api_url=base_url + "/stop_profile",
            prompt_len=test_prompt_len,
            output_len=test_output_len,
            logprobs=logprobs,
        )
        profile_output = await request_func(
            request_func_input=profile_input, session=session
        )
        if profile_output.success:
            print("Profiler stopped")

    await session.close()
    return result

calculate_metrics

calculate_metrics(
    input_requests: list[SampleRequest],
    outputs: list[RequestFuncOutput],
    dur_s: float,
    tokenizer: PreTrainedTokenizerBase,
    selected_percentiles: list[float],
    goodput_config_dict: dict[str, float],
) -> tuple[BenchmarkMetrics, list[int]]

Calculate the metrics for the benchmark.

Parameters:

Name Type Description Default
input_requests list[SampleRequest]

The input requests.

required
outputs list[RequestFuncOutput]

The outputs of the requests.

required
dur_s float

The duration of the benchmark.

required
tokenizer PreTrainedTokenizerBase

The tokenizer to use.

required
selected_percentiles list[float]

The percentiles to select.

required
goodput_config_dict dict[str, float]

The goodput configuration.

required

Returns:

Type Description
tuple[BenchmarkMetrics, list[int]]

A tuple of the benchmark metrics and the actual output lengths.

Source code in vllm/benchmarks/serve.py
def calculate_metrics(
    input_requests: list[SampleRequest],
    outputs: list[RequestFuncOutput],
    dur_s: float,
    tokenizer: PreTrainedTokenizerBase,
    selected_percentiles: list[float],
    goodput_config_dict: dict[str, float],
) -> tuple[BenchmarkMetrics, list[int]]:
    """Calculate the metrics for the benchmark.

    Args:
        input_requests: The input requests.
        outputs: The outputs of the requests.
        dur_s: The duration of the benchmark.
        tokenizer: The tokenizer to use.
        selected_percentiles: The percentiles to select.
        goodput_config_dict: The goodput configuration.

    Returns:
        A tuple of the benchmark metrics and the actual output lengths.
    """
    actual_output_lens: list[int] = []
    total_input = 0
    completed = 0
    good_completed = 0
    itls: list[float] = []
    tpots: list[float] = []
    all_tpots: list[float] = []
    ttfts: list[float] = []
    e2els: list[float] = []
    for i in range(len(outputs)):
        if outputs[i].success:
            output_len = outputs[i].output_tokens

            if not output_len:
                # We use the tokenizer to count the number of output tokens
                # for some serving backends instead of looking at
                # len(outputs[i].itl) since multiple output tokens may be
                # bundled together
                # Note : this may inflate the output token count slightly
                output_len = len(
                    tokenizer(
                        outputs[i].generated_text, add_special_tokens=False
                    ).input_ids
                )
            actual_output_lens.append(output_len)
            total_input += input_requests[i].prompt_len
            tpot = 0
            if output_len > 1:
                latency_minus_ttft = outputs[i].latency - outputs[i].ttft
                tpot = latency_minus_ttft / (output_len - 1)
                tpots.append(tpot)
            # Note: if output_len <= 1, we regard tpot as 0 for goodput
            all_tpots.append(tpot)
            itls += outputs[i].itl
            ttfts.append(outputs[i].ttft)
            e2els.append(outputs[i].latency)
            completed += 1
        else:
            actual_output_lens.append(0)

    if goodput_config_dict:
        valid_metrics = []
        slo_values = []

        if "ttft" in goodput_config_dict:
            valid_metrics.append(ttfts)
            slo_values.append(
                goodput_config_dict["ttft"] / MILLISECONDS_TO_SECONDS_CONVERSION
            )
        if "tpot" in goodput_config_dict:
            valid_metrics.append(all_tpots)
            slo_values.append(
                goodput_config_dict["tpot"] / MILLISECONDS_TO_SECONDS_CONVERSION
            )
        if "e2el" in goodput_config_dict:
            valid_metrics.append(e2els)
            slo_values.append(
                goodput_config_dict["e2el"] / MILLISECONDS_TO_SECONDS_CONVERSION
            )

        for req_metric in zip(*valid_metrics):
            is_good_req = all([s >= r for s, r in zip(slo_values, req_metric)])
            if is_good_req:
                good_completed += 1

    if completed == 0:
        warnings.warn(
            "All requests failed. This is likely due to a misconfiguration "
            "on the benchmark arguments.",
            stacklevel=2,
        )

    # Calculate max output tokens per second metric
    max_output_tokens_per_s = 0.0
    max_concurrent_requests = 0

    # Find the time range across all successful requests
    successful_outputs = [output for output in outputs if output.success]
    if successful_outputs:
        min_start_time = min(output.start_time for output in successful_outputs)
        max_end_time = max(
            output.start_time + output.latency for output in successful_outputs
        )

        # Create second buckets (ceiling to ensure we capture all time)
        duration_seconds = int(np.ceil(max_end_time - min_start_time)) + 1
        tokens_per_second = np.zeros(duration_seconds)
        concurrent_requests_per_second = np.zeros(duration_seconds)

        for i, output in enumerate(successful_outputs):
            # Calculate token generation timestamp using
            # start_time, ttft, and itl
            token_times = [output.start_time + output.ttft]
            current_time = token_times[0]
            for itl_value in output.itl:
                current_time += itl_value
                token_times.append(current_time)

            # Add tokens to second buckets
            for token_time in token_times:
                second_bucket = int(token_time - min_start_time)
                if 0 <= second_bucket < duration_seconds:
                    tokens_per_second[second_bucket] += 1

            # Track concurrent requests for each second this request was active
            request_start_second = int(output.start_time - min_start_time)
            request_end_second = int(
                (output.start_time + output.latency) - min_start_time
            )

            for second in range(request_start_second, request_end_second + 1):
                concurrent_requests_per_second[second] += 1

        # Find the maximum tokens per second and corresponding
        # concurrent requests
        if len(tokens_per_second) > 0:
            max_output_tokens_per_s = float(np.max(tokens_per_second))
            max_concurrent_requests = int(np.max(concurrent_requests_per_second))

        if TERM_PLOTLIB_AVAILABLE:
            import termplotlib as tpl

            fig = tpl.figure()
            fig.plot(
                np.arange(len(tokens_per_second)),
                tokens_per_second,
                title="Output tokens per second",
            )
            fig.plot(
                np.arange(len(concurrent_requests_per_second)),
                concurrent_requests_per_second,
                title="Concurrent requests per second",
            )
            fig.show()
        else:
            print("tip: install termplotlib and gnuplot to plot the metrics")

    metrics = BenchmarkMetrics(
        completed=completed,
        total_input=total_input,
        total_output=sum(actual_output_lens),
        request_throughput=completed / dur_s,
        request_goodput=good_completed / dur_s,
        output_throughput=sum(actual_output_lens) / dur_s,
        total_token_throughput=(total_input + sum(actual_output_lens)) / dur_s,
        mean_ttft_ms=np.mean(ttfts or 0)
        * 1000,  # ttfts is empty if streaming is not supported by the endpoint
        std_ttft_ms=np.std(ttfts or 0) * 1000,
        median_ttft_ms=np.median(ttfts or 0) * 1000,
        percentiles_ttft_ms=[
            (p, np.percentile(ttfts or 0, p) * 1000) for p in selected_percentiles
        ],
        mean_tpot_ms=np.mean(tpots or 0) * 1000,
        std_tpot_ms=np.std(tpots or 0) * 1000,
        median_tpot_ms=np.median(tpots or 0) * 1000,
        percentiles_tpot_ms=[
            (p, np.percentile(tpots or 0, p) * 1000) for p in selected_percentiles
        ],
        mean_itl_ms=np.mean(itls or 0) * 1000,
        std_itl_ms=np.std(itls or 0) * 1000,
        median_itl_ms=np.median(itls or 0) * 1000,
        percentiles_itl_ms=[
            (p, np.percentile(itls or 0, p) * 1000) for p in selected_percentiles
        ],
        mean_e2el_ms=np.mean(e2els or 0) * 1000,
        std_e2el_ms=np.std(e2els or 0) * 1000,
        median_e2el_ms=np.median(e2els or 0) * 1000,
        percentiles_e2el_ms=[
            (p, np.percentile(e2els or 0, p) * 1000) for p in selected_percentiles
        ],
        max_output_tokens_per_s=max_output_tokens_per_s,
        max_concurrent_requests=max_concurrent_requests,
    )

    return metrics, actual_output_lens

calculate_metrics_for_embeddings

calculate_metrics_for_embeddings(
    outputs: list[RequestFuncOutput],
    dur_s: float,
    selected_percentiles: list[float],
) -> EmbedBenchmarkMetrics

Calculate the metrics for the embedding requests.

Parameters:

Name Type Description Default
outputs list[RequestFuncOutput]

The outputs of the requests.

required
dur_s float

The duration of the benchmark.

required
selected_percentiles list[float]

The percentiles to select.

required

Returns:

Type Description
EmbedBenchmarkMetrics

The calculated benchmark metrics.

Source code in vllm/benchmarks/serve.py
def calculate_metrics_for_embeddings(
    outputs: list[RequestFuncOutput], dur_s: float, selected_percentiles: list[float]
) -> EmbedBenchmarkMetrics:
    """Calculate the metrics for the embedding requests.

    Args:
        outputs: The outputs of the requests.
        dur_s: The duration of the benchmark.
        selected_percentiles: The percentiles to select.

    Returns:
        The calculated benchmark metrics.
    """
    total_input = 0
    completed = 0
    e2els: list[float] = []
    for i in range(len(outputs)):
        if outputs[i].success:
            e2els.append(outputs[i].latency)
            completed += 1
            total_input += outputs[i].prompt_len

    if completed == 0:
        warnings.warn(
            "All requests failed. This is likely due to a misconfiguration "
            "on the benchmark arguments.",
            stacklevel=2,
        )
    metrics = EmbedBenchmarkMetrics(
        completed=completed,
        total_input=total_input,
        request_throughput=completed / dur_s,
        total_token_throughput=total_input / dur_s,
        mean_e2el_ms=np.mean(e2els or 0) * 1000,
        std_e2el_ms=np.std(e2els or 0) * 1000,
        median_e2el_ms=np.median(e2els or 0) * 1000,
        percentiles_e2el_ms=[
            (p, np.percentile(e2els or 0, p) * 1000) for p in selected_percentiles
        ],
    )
    return metrics

check_goodput_args

check_goodput_args(args)
Source code in vllm/benchmarks/serve.py
def check_goodput_args(args):
    # Check and parse goodput arguments
    goodput_config_dict = {}
    VALID_NAMES = ["ttft", "tpot", "e2el"]
    if args.goodput:
        goodput_config_dict = parse_goodput(args.goodput)
        for slo_name, slo_val in goodput_config_dict.items():
            if slo_name not in VALID_NAMES:
                raise ValueError(
                    f"Invalid metric name found, {slo_name}: {slo_val}. "
                    "The service level objective name should be one of "
                    f"{str(VALID_NAMES)}. "
                )
            if slo_val < 0:
                raise ValueError(
                    f"Invalid value found, {slo_name}: {slo_val}. "
                    "The service level objective value should be "
                    "non-negative."
                )
    return goodput_config_dict

get_request async

get_request(
    input_requests: list[SampleRequest],
    request_rate: float,
    burstiness: float = 1.0,
    ramp_up_strategy: Optional[
        Literal["linear", "exponential"]
    ] = None,
    ramp_up_start_rps: Optional[int] = None,
    ramp_up_end_rps: Optional[int] = None,
) -> AsyncGenerator[tuple[SampleRequest, float], None]

Asynchronously generates requests at a specified rate with OPTIONAL burstiness and OPTIONAL ramp-up strategy.

Parameters:

Name Type Description Default
input_requests list[SampleRequest]

A list of input requests, each represented as a SampleRequest.

required
request_rate float

The rate at which requests are generated (requests/s).

required
burstiness optional

The burstiness factor of the request generation. Only takes effect when request_rate is not inf. Default value is 1, which follows a Poisson process. Otherwise, the request intervals follow a gamma distribution. A lower burstiness value (0 < burstiness < 1) results in more bursty requests, while a higher burstiness value (burstiness > 1) results in a more uniform arrival of requests.

1.0
ramp_up_strategy optional

The ramp-up strategy. Can be "linear" or "exponential". If None, uses constant request rate (specified by request_rate).

None
ramp_up_start_rps optional

The starting request rate for ramp-up.

None
ramp_up_end_rps optional

The ending request rate for ramp-up.

None
Source code in vllm/benchmarks/serve.py
async def get_request(
    input_requests: list[SampleRequest],
    request_rate: float,
    burstiness: float = 1.0,
    ramp_up_strategy: Optional[Literal["linear", "exponential"]] = None,
    ramp_up_start_rps: Optional[int] = None,
    ramp_up_end_rps: Optional[int] = None,
) -> AsyncGenerator[tuple[SampleRequest, float], None]:
    """
    Asynchronously generates requests at a specified rate
    with OPTIONAL burstiness and OPTIONAL ramp-up strategy.

    Args:
        input_requests:
            A list of input requests, each represented as a SampleRequest.
        request_rate:
            The rate at which requests are generated (requests/s).
        burstiness (optional):
            The burstiness factor of the request generation.
            Only takes effect when request_rate is not inf.
            Default value is 1, which follows a Poisson process.
            Otherwise, the request intervals follow a gamma distribution.
            A lower burstiness value (0 < burstiness < 1) results
            in more bursty requests, while a higher burstiness value
            (burstiness > 1) results in a more uniform arrival of requests.
        ramp_up_strategy (optional):
            The ramp-up strategy. Can be "linear" or "exponential".
            If None, uses constant request rate (specified by request_rate).
        ramp_up_start_rps (optional):
            The starting request rate for ramp-up.
        ramp_up_end_rps (optional):
            The ending request rate for ramp-up.
    """
    assert burstiness > 0, (
        f"A positive burstiness factor is expected, but given {burstiness}."
    )
    # Convert to list to get length for ramp-up calculations
    if isinstance(input_requests, Iterable) and not isinstance(input_requests, list):
        input_requests = list(input_requests)

    total_requests = len(input_requests)
    assert total_requests > 0, "No requests provided."

    # Precompute delays among requests to minimize request send laggings
    request_rates = []
    delay_ts = []
    for request_index, request in enumerate(input_requests):
        current_request_rate = _get_current_request_rate(
            ramp_up_strategy,
            ramp_up_start_rps,
            ramp_up_end_rps,
            request_index,
            total_requests,
            request_rate,
        )
        request_rates.append(current_request_rate)
        if current_request_rate == float("inf"):
            delay_ts.append(0)
        else:
            theta = 1.0 / (current_request_rate * burstiness)

            # Sample the request interval from the gamma distribution.
            # If burstiness is 1, it follows exponential distribution.
            delay_ts.append(np.random.gamma(shape=burstiness, scale=theta))

    # Calculate the cumulative delay time from the first sent out requests.
    for i in range(1, len(delay_ts)):
        delay_ts[i] += delay_ts[i - 1]
    if ramp_up_strategy is None and delay_ts[-1] != 0:
        # When ramp_up_strategy is not set, we assume the request rate is fixed
        # and all requests should be sent in target_total_delay_s, the following
        # logic would re-scale delay time to ensure the final delay_ts
        # align with target_total_delay_s.
        #
        # NOTE: If we simply accumulate the random delta values
        # from the gamma distribution, their sum would have 1-2% gap
        # from target_total_delay_s. The purpose of the following logic is to
        # close the gap for stabilizing the throughput data
        # from different random seeds.
        target_total_delay_s = total_requests / request_rate
        normalize_factor = target_total_delay_s / delay_ts[-1]
        delay_ts = [delay * normalize_factor for delay in delay_ts]

    start_ts = time.time()
    for request_index, request in enumerate(input_requests):
        if delay_ts[request_index] > 0:
            current_ts = time.time()
            sleep_interval_s = start_ts + delay_ts[request_index] - current_ts
            if sleep_interval_s > 0:
                await asyncio.sleep(sleep_interval_s)
        yield request, request_rates[request_index]

main

main(args: Namespace) -> dict[str, Any]
Source code in vllm/benchmarks/serve.py
def main(args: argparse.Namespace) -> dict[str, Any]:
    return asyncio.run(main_async(args))

main_async async

main_async(args: Namespace) -> dict[str, Any]
Source code in vllm/benchmarks/serve.py
async def main_async(args: argparse.Namespace) -> dict[str, Any]:
    print(args)
    random.seed(args.seed)
    np.random.seed(args.seed)

    # Validate ramp-up arguments
    if args.ramp_up_strategy is not None:
        if args.request_rate != float("inf"):
            raise ValueError(
                "When using ramp-up, do not specify --request-rate. "
                "The request rate will be controlled by ramp-up parameters. "
                "Please remove the --request-rate argument."
            )
        if args.ramp_up_start_rps is None or args.ramp_up_end_rps is None:
            raise ValueError(
                "When using --ramp-up-strategy, both --ramp-up-start-rps and "
                "--ramp-up-end-rps must be specified"
            )
        if args.ramp_up_start_rps < 0 or args.ramp_up_end_rps < 0:
            raise ValueError("Ramp-up start and end RPS must be non-negative")
        if args.ramp_up_start_rps > args.ramp_up_end_rps:
            raise ValueError("Ramp-up start RPS must be less than end RPS")
        if args.ramp_up_strategy == "exponential" and args.ramp_up_start_rps == 0:
            raise ValueError("For exponential ramp-up, the start RPS cannot be 0.")

    label = args.label
    model_id = args.model
    model_name = args.served_model_name
    tokenizer_id = args.tokenizer if args.tokenizer is not None else args.model
    tokenizer_mode = args.tokenizer_mode

    if args.base_url is not None:
        api_url = f"{args.base_url}{args.endpoint}"
        base_url = f"{args.base_url}"
    else:
        api_url = f"http://{args.host}:{args.port}{args.endpoint}"
        base_url = f"http://{args.host}:{args.port}"

    # Headers
    headers = None
    if args.header:
        headers = {}
        for item in args.header:
            if "=" in item:
                kvstring = item.split("=", 1)
                headers[kvstring[0].strip()] = kvstring[1].strip()
            else:
                raise ValueError("Invalid header format. Please use KEY=VALUE format.")

    tokenizer = get_tokenizer(
        tokenizer_id,
        tokenizer_mode=tokenizer_mode,
        trust_remote_code=args.trust_remote_code,
    )

    if args.dataset_name is None:
        raise ValueError(
            "Please specify '--dataset-name' and the corresponding "
            "'--dataset-path' if required."
        )

    # Load the dataset.
    input_requests = get_samples(args, tokenizer)
    goodput_config_dict = check_goodput_args(args)

    backend = args.backend
    task_type = TaskType.EMBEDDING if "embeddings" in backend else TaskType.GENERATION

    # Collect the sampling parameters.
    if task_type == TaskType.GENERATION:
        sampling_params = {
            k: v
            for k, v in {
                "top_p": args.top_p,
                "top_k": args.top_k,
                "min_p": args.min_p,
                "temperature": args.temperature,
                "frequency_penalty": args.frequency_penalty,
                "presence_penalty": args.presence_penalty,
                "repetition_penalty": args.repetition_penalty,
            }.items()
            if v is not None
        }

        # Sampling parameters are only supported by openai-compatible backend.
        if sampling_params and args.backend not in OPENAI_COMPATIBLE_BACKENDS:
            raise ValueError(
                "Sampling parameters are only supported by openai-compatible backends."
            )

        if "temperature" not in sampling_params:
            sampling_params["temperature"] = 0.0  # Default to greedy decoding.
    else:
        sampling_params = {}

    # Avoid GC processing "static" data - reduce pause times.
    gc.collect()
    gc.freeze()

    benchmark_result = await benchmark(
        task_type=task_type,
        endpoint_type=backend,
        api_url=api_url,
        base_url=base_url,
        model_id=model_id,
        model_name=model_name,
        tokenizer=tokenizer,
        input_requests=input_requests,
        logprobs=args.logprobs,
        request_rate=args.request_rate,
        burstiness=args.burstiness,
        disable_tqdm=args.disable_tqdm,
        profile=args.profile,
        selected_percentile_metrics=args.percentile_metrics.split(","),
        selected_percentiles=[float(p) for p in args.metric_percentiles.split(",")],
        ignore_eos=args.ignore_eos,
        goodput_config_dict=goodput_config_dict,
        max_concurrency=args.max_concurrency,
        lora_modules=args.lora_modules,
        extra_headers=headers,
        extra_body=sampling_params,
        ramp_up_strategy=args.ramp_up_strategy,
        ramp_up_start_rps=args.ramp_up_start_rps,
        ramp_up_end_rps=args.ramp_up_end_rps,
        ready_check_timeout_sec=args.ready_check_timeout_sec,
    )

    # Save config and results to json
    result_json: dict[str, Any] = {}

    # Setup
    current_dt = datetime.now().strftime("%Y%m%d-%H%M%S")
    result_json["date"] = current_dt
    result_json["endpoint_type"] = args.backend  # for backward compatibility
    result_json["backend"] = args.backend
    result_json["label"] = label
    result_json["model_id"] = model_id
    result_json["tokenizer_id"] = tokenizer_id
    result_json["num_prompts"] = args.num_prompts

    # Metadata
    if args.metadata:
        for item in args.metadata:
            if "=" in item:
                kvstring = item.split("=", 1)
                result_json[kvstring[0].strip()] = kvstring[1].strip()
            else:
                raise ValueError(
                    "Invalid metadata format. Please use KEY=VALUE format."
                )

    # Traffic
    result_json["request_rate"] = (
        args.request_rate if args.request_rate < float("inf") else "inf"
    )
    result_json["burstiness"] = args.burstiness
    result_json["max_concurrency"] = args.max_concurrency

    if args.ramp_up_strategy is not None:
        result_json["ramp_up_strategy"] = args.ramp_up_strategy
        result_json["ramp_up_start_rps"] = args.ramp_up_start_rps
        result_json["ramp_up_end_rps"] = args.ramp_up_end_rps

    # Merge with benchmark result
    result_json = {**result_json, **benchmark_result}

    if not args.save_detailed:
        # Remove fields with too many data points
        for field in [
            "input_lens",
            "output_lens",
            "ttfts",
            "itls",
            "generated_texts",
            "errors",
        ]:
            if field in result_json:
                del result_json[field]
            if field in benchmark_result:
                del benchmark_result[field]

        # Save to file
    if args.save_result or args.append_result:
        base_model_id = model_id.split("/")[-1]
        max_concurrency_str = (
            f"-concurrency{args.max_concurrency}"
            if args.max_concurrency is not None
            else ""
        )
        label = label or args.backend
        if args.ramp_up_strategy is not None:
            file_name = f"{label}-ramp-up-{args.ramp_up_strategy}-{args.ramp_up_start_rps}qps-{args.ramp_up_end_rps}qps{max_concurrency_str}-{base_model_id}-{current_dt}.json"  # noqa
        else:
            file_name = f"{label}-{args.request_rate}qps{max_concurrency_str}-{base_model_id}-{current_dt}.json"  # noqa
        if args.result_filename:
            file_name = args.result_filename
        if args.result_dir:
            os.makedirs(args.result_dir, exist_ok=True)
            file_name = os.path.join(args.result_dir, file_name)
        with open(
            file_name, mode="a+" if args.append_result else "w", encoding="utf-8"
        ) as outfile:
            # Append a newline.
            if args.append_result and outfile.tell() != 0:
                outfile.write("\n")
            json.dump(result_json, outfile)
        save_to_pytorch_benchmark_format(args, result_json, file_name)

    return result_json

parse_goodput

parse_goodput(slo_pairs)
Source code in vllm/benchmarks/serve.py
def parse_goodput(slo_pairs):
    goodput_config_dict = {}
    try:
        for slo_pair in slo_pairs:
            slo_name, slo_val = slo_pair.split(":")
            goodput_config_dict[slo_name] = float(slo_val)
    except ValueError as err:
        raise argparse.ArgumentTypeError(
            "Invalid format found for service level objectives. "
            'Specify service level objectives for goodput as "KEY:VALUE" '
            "pairs, where the key is a metric name, and the value is a "
            "number in milliseconds."
        ) from err
    return goodput_config_dict

save_to_pytorch_benchmark_format

save_to_pytorch_benchmark_format(
    args: Namespace, results: dict[str, Any], file_name: str
) -> None
Source code in vllm/benchmarks/serve.py
def save_to_pytorch_benchmark_format(
    args: argparse.Namespace, results: dict[str, Any], file_name: str
) -> None:
    metrics = [
        "median_ttft_ms",
        "mean_ttft_ms",
        "std_ttft_ms",
        "p99_ttft_ms",
        "mean_tpot_ms",
        "median_tpot_ms",
        "std_tpot_ms",
        "p99_tpot_ms",
        "median_itl_ms",
        "mean_itl_ms",
        "std_itl_ms",
        "p99_itl_ms",
    ]
    # These raw data might be useful, but they are rather big. They can be added
    # later if needed
    ignored_metrics = ["ttfts", "itls", "generated_texts", "errors"]
    pt_records = convert_to_pytorch_benchmark_format(
        args=args,
        metrics={k: [results[k]] for k in metrics if k in results},
        extra_info={
            k: results[k]
            for k in results
            if k not in metrics and k not in ignored_metrics
        },
    )
    if pt_records:
        # Don't use json suffix here as we don't want CI to pick it up
        pt_file = f"{os.path.splitext(file_name)[0]}.pytorch.json"
        write_to_json(pt_file, pt_records)