Model Serving Infrastructure: Core Control Loop and Architecture Patterns
The Core Challenge
The real complexity lies not in setting up endpoints but in three critical areas: resource scheduling across models and hardware, memory management balancing batch sizes against device capacity, and rollout safety through versioning and traffic splitting.
Three Architectural Patterns
Framework specific servers like TensorFlow Serving or TorchServe provide tight integration with a single framework, simpler mental models, and fewer moving parts. Multi backend servers like Triton abstract the runtime layer, enabling a single control plane across TensorFlow, PyTorch, ONNX, and hardware optimized backends like TensorRT or OpenVINO. This unified approach adds powerful scheduling features like dynamic batching and model ensembles but increases configuration complexity. Custom thin servers give maximum control but require building your own scheduling, observability, and deployment mechanisms from scratch.
The Fundamental Trade-off
Throughput versus latency is governed by batching and concurrency decisions. Dynamic batching aggregates requests to improve device utilization (more predictions per second), while per model concurrency controls parallel instances. Preprocessing placement determines whether you become CPU bound or accelerator bound. Precision conversions from FP32 to FP16/BF16 or INT8 trade small accuracy drops for significant throughput gains.
Production Reality
Real world benchmarks reveal optimization importance: on a V100 GPU running ResNet50 on 32,000 images, raw TensorFlow completed in 83 to 87 seconds (368 to 386 images per second), TensorFlow Serving took 117 to 120 seconds (267 to 274 images per second), and untuned Triton required 171 to 202 seconds (158 to 187 images per second). Serving infrastructure overhead can reduce throughput by 30% to 50% without proper tuning.