Python API¶
通过 Python API 直接以编程方式访问 vllm-mlx。
Language Models¶
基本用法¶
from vllm_mlx.models import MLXLanguageModel
# Load model
model = MLXLanguageModel("mlx-community/Llama-3.2-3B-Instruct-4bit")
model.load()
# Generate text
output = model.generate("What is the capital of France?", max_tokens=100)
print(output.text)
Streaming Generation¶
for chunk in model.stream_generate("Tell me a story about a robot"):
print(chunk.text, end="", flush=True)
Chat 接口¶
messages = [
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Hello, who are you?"}
]
response = model.chat(messages)
print(response.text)
生成参数¶
output = model.generate(
prompt="Write a poem",
max_tokens=256,
temperature=0.7,
top_p=0.9,
stop=["END", "\n\n"]
)
| 参数 | 描述 | 默认值 |
|---|---|---|
max_tokens |
最大生成 token 数量 | 256 |
temperature |
采样温度(0-2) | 0.7 |
top_p |
Nucleus sampling | 0.9 |
stop |
停止序列 | None |
Vision-Language Models¶
基本用法¶
from vllm_mlx.models import MLXMultimodalLM
# Load model
mllm = MLXMultimodalLM("mlx-community/Qwen3-VL-4B-Instruct-3bit")
mllm.load()
# Describe an image
description = mllm.describe_image("photo.jpg")
print(description)
问答¶
多图片输入¶
output = mllm.generate(
prompt="Compare these two images",
images=["image1.jpg", "image2.jpg"]
)
print(output.text)
视频理解¶
# From local file
output = mllm.generate(
prompt="What is happening in this video?",
videos=["video.mp4"],
video_fps=2.0,
video_max_frames=16
)
print(output.text)
# From URL
output = mllm.generate(
prompt="Describe this video",
videos=["https://example.com/video.mp4"],
video_fps=2.0
)
# Convenience method
description = mllm.describe_video("video.mp4", fps=2.0)
视频参数¶
| 参数 | 描述 | 默认值 |
|---|---|---|
video_fps |
每秒提取帧数 | 2.0 |
video_max_frames |
最大处理帧数 | 32 |
Engine API¶
针对高级使用场景,可直接使用 engine:
Simple Engine¶
from vllm_mlx.engine import SimpleEngine
engine = SimpleEngine("mlx-community/Llama-3.2-3B-Instruct-4bit")
await engine.start()
output = await engine.generate(
prompt="Hello world",
max_tokens=100
)
print(output.text)
await engine.stop()
Batched Engine¶
from vllm_mlx.engine import BatchedEngine
engine = BatchedEngine("mlx-community/Llama-3.2-3B-Instruct-4bit")
await engine.start()
# Multiple concurrent requests
output = await engine.generate(
prompt="Hello world",
max_tokens=100
)
await engine.stop()
输出格式¶
所有生成方法均返回 GenerationOutput:
output = model.generate("Hello")
print(output.text) # Generated text
print(output.prompt_tokens) # Input token count
print(output.completion_tokens) # Output token count
print(output.finish_reason) # "stop" or "length"