TL;DR

Miles v0.1 describes a full-stack post-training system spanning rollout generation, optimization, and weight synchronization. Its reference run demonstrates asynchronous terminal-agent RL with a 744B-parameter MoE model and makes the system’s supported configurations explicit.

Why it matters

Scaling RL requires coordinating generation, environment execution, training, and synchronization. A concrete system report helps explain how numerical fidelity and resource scheduling determine whether theoretical compute capacity becomes useful training throughput.

Key findings

  1. 01

    The system builds on slime with SGLang rollouts, Megatron-LM or FSDP training, and multiple weight-update transports. It also supports LoRA RL, on-policy distillation, supervised fine-tuning, and an extension to diffusion models.

  2. 02

    Token-in-token-out trajectories preserve sampled token identifiers, while rollout routing replay records MoE expert choices. These mechanisms address mismatches that can arise when multi-turn trajectories are reconstructed or processed by different engines.

  3. 03

    The reference case trains GLM-5.2, with 744B total and 40B active parameters, on terminal-use tasks using 64 GB300 GPUs split equally between rollout and training. The run uses asynchronous scheduling and supports sessions up to 65,536 tokens.

  4. 04

    The median training step is 263 seconds over the first 30 measured steps. Across the single 100-step run, reported rollout–training divergence averages 0.0369; raw reward’s nine-step moving average rises from 0.438 to 0.556, which the authors explicitly report as an observation rather than a measured improvement.

  • The throughput figure belongs to one hardware, model, and task configuration. The 1,042-second warm-up at step zero is clipped from the plotted range, and the reported median does not summarize all end-to-end setup costs.

  • A single 100-step run cannot separate reward changes from run-to-run variation. The case study does not establish a general capability gain or a universal speed advantage over other RL systems.

  • Supported scope varies by component. The report identifies incomplete vision-language session support, early-stage precision formats, and weight-transfer paths covering only some model families.

Scaling dimensions

Models, methods & benchmarks

Models
GLM-5.2
Algorithms
Asynchronous RL, Rollout routing replay, Token-in-token-out, On-Policy Distillation
Benchmarks
Terminal-use coding tasks

Topics

Read the original sourcearXiv ↗