FastRL pruned low-information rollouts and sped up GRPO-family training 2.07x while adding about 1.64 percent accuracy on visual reasoning
AspireAI community · arXiv (2609.36932)
Reinforcement learning with verifiable rewards burns compute on rollouts that teach nothing, so FastRL attacks the sampling step instead of the reward. It keeps only the high-advantage trajectories while maximizing the diversity of the gradients between them, and then adjusts how many rollouts it draws at each training stage based on how those trajectories were pruned previously, so exploration budget stays proportional to what is still useful. The authors report that this plugs into GRPO, DAPO and GSPO without changes and delivers an average 2.07x training speedup on Geometry3K and GeoQA8K-R1V alongside roughly 1.64 percent higher average accuracy on visual reasoning. The honest caveat is the domain: the speedup and the accuracy bump are both measured on visual-reasoning benchmarks rather than general text reasoning, and the abstract says code 'will be available' rather than pointing at a repository.
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