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vLLM CLI Guide

The vllm command-line tool is used to run and manage vLLM models. You can start by viewing the help message with:

vllm --help

Available Commands:

vllm {chat,complete,serve,bench,collect-env,run-batch}

serve

Start the vLLM OpenAI Compatible API server.

Examples
# Start with a model
vllm serve meta-llama/Llama-2-7b-hf

# Specify the port
vllm serve meta-llama/Llama-2-7b-hf --port 8100

# Check with --help for more options
# To list all groups
vllm serve --help=listgroup

# To view a argument group
vllm serve --help=ModelConfig

# To view a single argument
vllm serve --help=max-num-seqs

# To search by keyword
vllm serve --help=max

chat

Generate chat completions via the running API server.

# Directly connect to localhost API without arguments
vllm chat

# Specify API url
vllm chat --url http://{vllm-serve-host}:{vllm-serve-port}/v1

# Quick chat with a single prompt
vllm chat --quick "hi"

complete

Generate text completions based on the given prompt via the running API server.

# Directly connect to localhost API without arguments
vllm complete

# Specify API url
vllm complete --url http://{vllm-serve-host}:{vllm-serve-port}/v1

# Quick complete with a single prompt
vllm complete --quick "The future of AI is"

bench

Run benchmark tests for latency online serving throughput and offline inference throughput.

To use benchmark commands, please install with extra dependencies using pip install vllm[bench].

Available Commands:

vllm bench {latency, serve, throughput}

latency

Benchmark the latency of a single batch of requests.

vllm bench latency \
    --model meta-llama/Llama-3.2-1B-Instruct \
    --input-len 32 \
    --output-len 1 \
    --enforce-eager \
    --load-format dummy

serve

Benchmark the online serving throughput.

vllm bench serve \
    --model meta-llama/Llama-3.2-1B-Instruct \
    --host server-host \
    --port server-port \
    --random-input-len 32 \
    --random-output-len 4  \
    --num-prompts  5

throughput

Benchmark offline inference throughput.

vllm bench throughput \
    --model meta-llama/Llama-3.2-1B-Instruct \
    --input-len 32 \
    --output-len 1 \
    --enforce-eager \
    --load-format dummy

collect-env

Start collecting environment information.

vllm collect-env

run-batch

Run batch prompts and write results to file.

Examples
# Running with a local file
vllm run-batch \
    -i offline_inference/openai_batch/openai_example_batch.jsonl \
    -o results.jsonl \
    --model meta-llama/Meta-Llama-3-8B-Instruct

# Using remote file
vllm run-batch \
    -i https://raw.githubusercontent.com/vllm-project/vllm/main/examples/offline_inference/openai_batch/openai_example_batch.jsonl \
    -o results.jsonl \
    --model meta-llama/Meta-Llama-3-8B-Instruct

More Help

For detailed options of any subcommand, use:

vllm <subcommand> --help