Inference

Table of Contents Introduction Why Scaling LLM Inference Is Hard Overview of Ray and Its Role in Distributed Inference Kubernetes as the Orchestration Backbone Architectural Blueprint: Ray on Kubernetes Step‑by‑Step Implementation 6.1 Preparing the Model Container 6.2 Deploying a Ray Cluster on K8s 6.3 Writing the Inference Service 6.4 Autoscaling with Ray Autoscaler & K8s HPA 6.5 Observability & Monitoring Real‑World Production Considerations 7.1 GPU Allocation Strategies 7.2 Model Versioning & Rolling Updates 7.3 Security & Multi‑Tenant Isolation Performance Benchmarks & Cost Analysis Conclusion Resources Introduction Large language models (LLMs) such as GPT‑3, Llama 2, and Claude have moved from research curiosities to production‑critical components that power chatbots, code assistants, summarizers, and many other AI‑driven services. While training these models demands massive clusters and weeks of compute, serving them in real time presents a different set of engineering challenges: ...

Table of contents Introduction What is quantization (simple explanation) Why quantize LLMs? Costs, memory, and latency Quantization primitives and concepts Precision (bit widths) Range, scale and zero-point Uniform vs non-uniform quantization Blockwise and per-channel scaling Main quantization workflows Post-Training Quantization (PTQ) Quantization-Aware Training (QAT) Hybrid and mixed-precision approaches Practical algorithms and techniques Linear (symmetric) quantization Affine (zero-point) quantization Blockwise / groupwise quantization K-means and non-uniform quantization Persistent or learned scales, GPTQ-style (second-order aware) methods Quantizing KV caches and activations Tools, libraries and ecosystem (how to get started) Bitsandbytes, GGML, Hugging Face & Quanto, PyTorch, GPTQ implementations End-to-end example: quantize a transformer weight matrix (code) Best practices and debugging tips Limitations and failure modes Future directions Conclusion Resources Introduction Quantization reduces the numeric precision of a model’s parameters (and sometimes activations) so that a trained Large Language Model (LLM) needs fewer bits to store and compute with its values. The result: much smaller models, lower memory use, faster inference, and often reduced cost with only modest accuracy loss when done well[2][5]. ...