What problem does it solve?
slime streamlines LLM reinforcement-learning post-training by connecting Megatron-LM training with SGLang rollout generation, reducing the complexity of building an RL system that needs high-throughput sampling and tight training/inference integration.
Core Features & Use Cases
- Megatron-LM + SGLang orchestration: Runs actor (and optional critic) training in Megatron-LM while generating rollouts with SGLang and a router for throughput.
- GRPO and related RL algorithms: Supports group-relative advantage estimation and common RL objective variants with KL loss control for stability.
- Flexible data buffer and rollout reuse: Uses a data buffer system to manage prompts, store rollouts, and optionally filter/reselect samples for off-policy style training.
- Use Case: Post-train a GLM/Qwen/DeepSeek/Llama-style model on reasoning or preference signals by repeatedly generating candidate responses, scoring them with a verifier/reward function, and training with bounded rollout/fix loops until performance improves.
Quick Start
Run slime with GRPO training by providing your JSONL dataset and selecting a model script (e.g., qwen3-4B) to start training and rollout generation in a single coordinated workflow.