Files
vllm/cacheflow/sampling_params.py
2023-05-11 15:45:30 -07:00

89 lines
3.3 KiB
Python

from typing import Dict, Set
class SamplingParams:
def __init__(
self,
n: int = 1,
presence_penalty: float = 0.0,
frequency_penalty: float = 0.0,
temperature: float = 1.0,
top_p: float = 1.0,
top_k: int = -1,
use_beam_search: bool = False,
stop_token_ids: Set[int] = set(),
max_tokens: int = 16,
logprobs: int = 0,
) -> None:
if n < 1:
raise ValueError(f"n must be at least 1, got {n}.")
if not -2.0 <= presence_penalty <= 2.0:
raise ValueError(
f"presence_penalty must be in [-2, 2], got {presence_penalty}.")
if not -2.0 <= frequency_penalty <= 2.0:
raise ValueError(
f"frequency_penalty must be in [-2, 2], got {frequency_penalty}.")
if temperature < 0.0:
raise ValueError(
f"temperature must be non-negative, got {temperature}.")
if not 0.0 < top_p <= 1.0:
raise ValueError(f"top_p must be in (0, 1], got {top_p}.")
if top_k < -1 or top_k == 0:
raise ValueError(f"top_k must be -1 (disable), or at least 1, "
f"got {top_k}.")
if max_tokens < 1:
raise ValueError(
f"max_tokens must be at least 1, got {max_tokens}.")
if logprobs < 0:
raise ValueError(
f"logprobs must be non-negative, got {logprobs}.")
if use_beam_search:
if n == 1:
raise ValueError(
"n must be greater than 1 when using beam search.")
if temperature > 0.0:
raise ValueError(
"temperature must be 0 when using beam search.")
if top_p < 1.0:
raise ValueError(
"top_p must be 1 when using beam search.")
if top_k != -1:
raise ValueError(
"top_k must be -1 when using beam search.")
elif temperature == 0.0:
# Zero temperature means greedy sampling.
if n > 1:
raise ValueError(
"n must be 1 when using greedy sampling.")
if top_p < 1.0:
raise ValueError(
"top_p must be 1 when using greedy sampling.")
if top_k != -1:
raise ValueError(
"top_k must be -1 when using greedy sampling.")
self.n = n
self.presence_penalty = presence_penalty
self.frequency_penalty = frequency_penalty
self.temperature = temperature
self.top_p = top_p
self.top_k = top_k
self.use_beam_search = use_beam_search
self.stop_token_ids = stop_token_ids
self.max_tokens = max_tokens
self.logprobs = logprobs
def __repr__(self) -> str:
return (f"SamplingParams(n={self.n}, "
f"presence_penalty={self.presence_penalty}, "
f"frequency_penalty={self.frequency_penalty}, "
f"temperature={self.temperature}, "
f"top_p={self.top_p}, "
f"top_k={self.top_k},"
f"use_beam_search={self.use_beam_search}, "
f"stop_token_ids={self.stop_token_ids}, "
f"max_tokens={self.max_tokens}, "
f"logprobs={self.logprobs}")