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vllm.engine.metrics_types

These types are defined in this file to avoid importing vllm.engine.metrics and therefore importing prometheus_client.

This is required due to usage of Prometheus multiprocess mode to enable metrics after splitting out the uvicorn process from the engine process.

Prometheus multiprocess mode requires setting PROMETHEUS_MULTIPROC_DIR before prometheus_client is imported. Typically, this is done by setting the env variable before launch, but since we are a library, we need to do this in Python code and lazily import prometheus_client.

StatLoggerBase

Bases: ABC

Base class for StatLogger.

Source code in vllm/engine/metrics_types.py 
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class StatLoggerBase(ABC):
    """Base class for StatLogger."""

    def __init__(self, local_interval: float, vllm_config: VllmConfig) -> None:
        # Tracked stats over current local logging interval.
        self.num_prompt_tokens: List[int] = []
        self.num_generation_tokens: List[int] = []
        self.last_local_log = time.time()
        self.local_interval = local_interval

    @abstractmethod
    def log(self, stats: Stats) -> None:
        raise NotImplementedError

    @abstractmethod
    def info(self, type: str, obj: SupportsMetricsInfo) -> None:
        raise NotImplementedError

last_local_log instance-attribute 

last_local_log = time()

local_interval instance-attribute 

local_interval = local_interval

num_generation_tokens instance-attribute 

num_generation_tokens: List[int] = []

num_prompt_tokens instance-attribute 

num_prompt_tokens: List[int] = []

__init__ 

__init__(
    local_interval: float, vllm_config: VllmConfig
) -> None
Source code in vllm/engine/metrics_types.py 
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def __init__(self, local_interval: float, vllm_config: VllmConfig) -> None:
    # Tracked stats over current local logging interval.
    self.num_prompt_tokens: List[int] = []
    self.num_generation_tokens: List[int] = []
    self.last_local_log = time.time()
    self.local_interval = local_interval

info abstractmethod 

info(type: str, obj: SupportsMetricsInfo) -> None
Source code in vllm/engine/metrics_types.py 
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@abstractmethod
def info(self, type: str, obj: SupportsMetricsInfo) -> None:
    raise NotImplementedError

log abstractmethod 

log(stats: Stats) -> None
Source code in vllm/engine/metrics_types.py 
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@abstractmethod
def log(self, stats: Stats) -> None:
    raise NotImplementedError

Stats dataclass

Created by LLMEngine for use by StatLogger.

Source code in vllm/engine/metrics_types.py 
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@dataclass
class Stats:
    """Created by LLMEngine for use by StatLogger."""
    now: float

    # System stats (should have _sys suffix)
    #   Scheduler State
    num_running_sys: int
    num_waiting_sys: int
    num_swapped_sys: int
    #   KV Cache Usage in %
    gpu_cache_usage_sys: float
    cpu_cache_usage_sys: float
    #   Prefix caching block hit rate
    cpu_prefix_cache_hit_rate: float
    gpu_prefix_cache_hit_rate: float

    # Iteration stats (should have _iter suffix)
    num_prompt_tokens_iter: int
    num_generation_tokens_iter: int
    num_tokens_iter: int
    time_to_first_tokens_iter: List[float]
    inter_token_latencies_iter: List[float]
    num_preemption_iter: int

    # Request stats (should have _requests suffix)
    #   Latency
    time_e2e_requests: List[float]
    time_queue_requests: List[float]
    time_inference_requests: List[float]
    time_prefill_requests: List[float]
    time_decode_requests: List[float]
    #   Metadata
    num_prompt_tokens_requests: List[int]
    num_generation_tokens_requests: List[int]
    n_requests: List[int]
    max_num_generation_tokens_requests: List[int]
    max_tokens_requests: List[int]
    finished_reason_requests: List[str]
    waiting_lora_adapters: List[str]
    running_lora_adapters: List[str]
    max_lora: str

cpu_cache_usage_sys instance-attribute 

cpu_cache_usage_sys: float

cpu_prefix_cache_hit_rate instance-attribute 

cpu_prefix_cache_hit_rate: float

finished_reason_requests instance-attribute 

finished_reason_requests: List[str]

gpu_cache_usage_sys instance-attribute 

gpu_cache_usage_sys: float

gpu_prefix_cache_hit_rate instance-attribute 

gpu_prefix_cache_hit_rate: float

inter_token_latencies_iter instance-attribute 

inter_token_latencies_iter: List[float]

max_lora instance-attribute 

max_lora: str

max_num_generation_tokens_requests instance-attribute 

max_num_generation_tokens_requests: List[int]

max_tokens_requests instance-attribute 

max_tokens_requests: List[int]

n_requests instance-attribute 

n_requests: List[int]

now instance-attribute 

now: float

num_generation_tokens_iter instance-attribute 

num_generation_tokens_iter: int

num_generation_tokens_requests instance-attribute 

num_generation_tokens_requests: List[int]

num_preemption_iter instance-attribute 

num_preemption_iter: int

num_prompt_tokens_iter instance-attribute 

num_prompt_tokens_iter: int

num_prompt_tokens_requests instance-attribute 

num_prompt_tokens_requests: List[int]

num_running_sys instance-attribute 

num_running_sys: int

num_swapped_sys instance-attribute 

num_swapped_sys: int

num_tokens_iter instance-attribute 

num_tokens_iter: int

num_waiting_sys instance-attribute 

num_waiting_sys: int

running_lora_adapters instance-attribute 

running_lora_adapters: List[str]

time_decode_requests instance-attribute 

time_decode_requests: List[float]

time_e2e_requests instance-attribute 

time_e2e_requests: List[float]

time_inference_requests instance-attribute 

time_inference_requests: List[float]

time_prefill_requests instance-attribute 

time_prefill_requests: List[float]

time_queue_requests instance-attribute 

time_queue_requests: List[float]

time_to_first_tokens_iter instance-attribute 

time_to_first_tokens_iter: List[float]

waiting_lora_adapters instance-attribute 

waiting_lora_adapters: List[str]

__init__ 

__init__(
    now: float,
    num_running_sys: int,
    num_waiting_sys: int,
    num_swapped_sys: int,
    gpu_cache_usage_sys: float,
    cpu_cache_usage_sys: float,
    cpu_prefix_cache_hit_rate: float,
    gpu_prefix_cache_hit_rate: float,
    num_prompt_tokens_iter: int,
    num_generation_tokens_iter: int,
    num_tokens_iter: int,
    time_to_first_tokens_iter: List[float],
    inter_token_latencies_iter: List[float],
    num_preemption_iter: int,
    time_e2e_requests: List[float],
    time_queue_requests: List[float],
    time_inference_requests: List[float],
    time_prefill_requests: List[float],
    time_decode_requests: List[float],
    num_prompt_tokens_requests: List[int],
    num_generation_tokens_requests: List[int],
    n_requests: List[int],
    max_num_generation_tokens_requests: List[int],
    max_tokens_requests: List[int],
    finished_reason_requests: List[str],
    waiting_lora_adapters: List[str],
    running_lora_adapters: List[str],
    max_lora: str,
) -> None