Request Schedulers — Inference Engines

vLLM is a high-throughput inference engine designed for the efficient serving and execution of large language models. It functions as a production-ready distributed model server, providing standard API protocols for online serving while also supporting offline batch processing. The system is built to maximize token generation speed and memory efficiency, enabling both large-scale cloud deployments and local execution on personal hardware. The project distinguishes itself through advanced memory management and request scheduling techniques, most notably its use of non-contiguous key-value cache blocks to eliminate fragmentation and its ability to dynamically insert new sequences into batches as they arrive. It provides a hardware-agnostic abstraction layer that maps complex mathematical operations to diverse accelerators, including specialized GPUs and consumer-grade silicon like Apple hardware. This is further supported by custom kernel fusion and a flexible quantization framework that allows for the compression of neural networks to fit resource-constrained environments. Beyond its core runtime, the framework offers extensive support for custom