Machine Heart

May 1, 2026 · Artificial Intelligence

From PPO to MaxRL: The Evolution of Reinforcement Learning for LLM Inference

This article surveys the rapid evolution of reinforcement‑learning algorithms for large‑language‑model inference from early REINFORCE and PPO to newer approaches such as GRPO, RLOO, DAPO, CISPO, DPPO, ScaleRL and MaxRL, highlighting their design motivations, mathematical formulations, empirical trade‑offs and open research challenges.