Introducing Disaggregated Inference on AWS powered by llm-d
Summary
AWS has partnered with the llm-d team to integrate disaggregated inference capabilities into AWS services, enhancing performance and cost efficiency for large-scale LLM inference workloads. This collaboration introduces a new container, `ghcr.io/llm-d/llm-d-aws`, which includes AWS-specific libraries like Elastic Fabric Adapter (EFA) and libfabric, alongside NIXL integration for multi-node disaggregated inference and expert parallelism. The llm-d framework, built on vLLM, is Kubernetes-native and optimizes LLM serving by separating prefill and decode phases, enabling intelligent request scheduling, and supporting tiered prefix caching. Benchmarking shows that llm-d's prefill/decode disaggregation can increase tokens per second by up to 70% compared to standard vLLM deployments under specific load conditions, particularly for workloads with long input and output sequences.
Key takeaway
For MLOps Engineers deploying large language models at scale on AWS, adopting llm-d's disaggregated inference architecture on Amazon SageMaker HyperPod or EKS can significantly improve throughput and reduce costs. You should explore configuring prefill/decode disaggregation and intelligent scheduling to optimize resource utilization and achieve up to 70% higher tokens per second for agentic or long-sequence workloads.
Key insights
Disaggregated LLM inference on AWS significantly boosts performance and resource utilization for large-scale AI deployments.
Principles
- Separate compute-bound prefill from memory-bound decode.
- Utilize cache-aware routing for distributed LLM inference.
- Offload KV cache entries beyond GPU memory limits.
Method
llm-d orchestrates distributed LLM serving by disaggregating prefill and decode phases, employing intelligent, cache-aware scheduling, and leveraging high-speed interconnects like EFA via NIXL for efficient KV cache transfers.
In practice
- Deploy llm-d on Amazon SageMaker HyperPod or EKS.
- Configure EFA interfaces for high-bandwidth GPU communication.
- Tune prefill/decode ratios for specific workload characteristics.
Topics
- LLM Inference Optimization
- Disaggregated Serving
- Kubernetes
- vLLM
- Elastic Fabric Adapter
Code references
Best for: MLOps Engineer, AI Engineer, Machine Learning Engineer
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Editorial summary, takeaway, and curation by AIssential. Original article published by Artificial Intelligence.