inference-serving-tensorrt-llm

TensorRT-LLM

NVIDIA's open-source library for optimizing LLM inference with state-of-the-art performance on NVIDIA GPUs.

When to use TensorRT-LLM

Use TensorRT-LLM when:

• Deploying on NVIDIA GPUs (A100, H100, GB200)
• Need maximum throughput (24,000+ tokens/sec on Llama 3)
• Require low latency for real-time applications
• Working with quantized models (FP8, INT4, FP4)
• Scaling across multiple GPUs or nodes

Use vLLM instead when:

• Need simpler setup and Python-first API
• Want PagedAttention without TensorRT compilation
• Working with AMD GPUs or non-NVIDIA hardware

Use llama.cpp instead when:

• Deploying on CPU or Apple Silicon
• Need edge deployment without NVIDIA GPUs
• Want simpler GGUF quantization format

Quick start

Installation

# Docker (recommended)
docker pull nvidia/tensorrt_llm:latest

# pip install
pip install tensorrt_llm==1.2.0rc3

# Requires CUDA 13.0.0, TensorRT 10.13.2, Python 3.10-3.12

Basic inference

from tensorrt_llm import LLM, SamplingParams

# Initialize model
llm = LLM(model="meta-llama/Meta-Llama-3-8B")

# Configure sampling
sampling_params = SamplingParams(
    max_tokens=100,
    temperature=0.7,
    top_p=0.9
)

# Generate
prompts = ["Explain quantum computing"]
outputs = llm.generate(prompts, sampling_params)

for output in outputs:
    print(output.text)

Serving with trtllm-serve

# Start server (automatic model download and compilation)
trtllm-serve meta-llama/Meta-Llama-3-8B \
    --tp_size 4 \              # Tensor parallelism (4 GPUs)
    --max_batch_size 256 \
    --max_num_tokens 4096

# Client request
curl -X POST http://localhost:8000/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "meta-llama/Meta-Llama-3-8B",
    "messages": [{"role": "user", "content": "Hello!"}],
    "temperature": 0.7,
    "max_tokens": 100
  }'

Key features

Performance optimizations

• In-flight batching: Dynamic batching during generation
• Paged KV cache: Efficient memory management
• Flash Attention: Optimized attention kernels
• Quantization: FP8, INT4, FP4 for 2-4× faster inference
• CUDA graphs: Reduced kernel launch overhead