Scaling AI Inference Across Multiple GPUs Using NVIDIA TensorRT with Multi-Device Inference Support
Summary
NVIDIA TensorRT 11.0 introduces multi-device inference support, enabling generative AI workloads to scale beyond single-GPU memory and compute limitations. This new feature integrates with NVIDIA NCCL, leveraging its high-performance collective operations like AllReduce and AllGather for distributed inference. The article details two primary parallelism strategies: tensor parallelism, which partitions model weights across GPUs, and context parallelism, which partitions input sequences. For context parallelism, three specific implementations are discussed: AllGather KV, Ring Attention, and DeepSpeed Ulysses. Benchmarks conducted on a single node with 8 GPUs using NVIDIA Cosmos 3 for video generation and FLUX.1 for image generation demonstrated that the Ulysses strategy consistently delivered the lowest end-to-end latency, especially for models with excessively long context lengths, while Ring Attention also showed good scaling for FLUX.1. This allows developers to deploy massive PyTorch models converted via Torch-TensorRT into C++ production environments.
Key takeaway
For AI Engineers scaling generative AI models that exceed single-GPU capacity, NVIDIA TensorRT 11.0's multi-device inference support provides a critical solution. You should integrate this feature, leveraging its native NCCL-powered distributed collective operations and exploring context parallelism strategies like DeepSpeed Ulysses. This enables efficient deployment of large PyTorch models, converted via Torch-TensorRT, into C++ production environments, significantly reducing latency for long-sequence workloads.
Key insights
TensorRT 11.0 scales generative AI inference across multiple GPUs using NCCL and parallelism strategies.
Principles
- Generative AI models frequently exceed single-GPU memory and compute.
- Distributed inference employs strategies like tensor and context parallelism.
- NVIDIA NCCL optimizes multi-GPU collective communication for inference.
Method
Create a TensorRT network with "IDistCollectiveLayer" for collectives, build the engine, set the NCCL communicator, and enqueue inference, running with OpenMPI.
In practice
- Download TensorRT 11.0 and install OpenMPI for multi-GPU setups.
- Convert PyTorch models using Torch-TensorRT for optimized deployment.
- Evaluate Ulysses for long-context generative media pipelines.
Topics
- NVIDIA TensorRT
- Multi-GPU Inference
- Context Parallelism
- Generative AI
- NVIDIA NCCL
- DeepSpeed Ulysses
Code references
Best for: AI Engineer, Machine Learning Engineer, AI Architect
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Editorial summary, takeaway, and curation by AIssential. Original article published by NVIDIA Technical Blog.