How to Allocate, How to Learn? Dynamic Rollout Allocation and Advantage Modulation for Policy Optimization
- URL: http://arxiv.org/abs/2602.19208v1
- Date: Sun, 22 Feb 2026 14:38:24 GMT
- Title: How to Allocate, How to Learn? Dynamic Rollout Allocation and Advantage Modulation for Policy Optimization
- Authors: Yangyi Fang, Jiaye Lin, Xiaoliang Fu, Cong Qin, Haolin Shi, Chaowen Hu, Lu Pan, Ke Zeng, Xunliang Cai,
- Abstract summary: DynaMO is a theoretically-grounded dual-pronged optimization framework.<n>We develop gradient-aware advantage modulation grounded in theoretical analysis of gradient magnitude bounds.<n>Our framework compensates for gradient attenuation of high-confidence correct actions while utilizing entropy changes as computable indicators to stabilize excessive update magnitudes.
- Score: 14.087451720550597
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Reinforcement Learning with Verifiable Rewards (RLVR) has proven effective for Large Language Model (LLM) reasoning, yet current methods face key challenges in resource allocation and policy optimization dynamics: (i) uniform rollout allocation ignores gradient variance heterogeneity across problems, and (ii) the softmax policy structure causes gradient attenuation for high-confidence correct actions, while excessive gradient updates may destabilize training. Therefore, we propose DynaMO, a theoretically-grounded dual-pronged optimization framework. At the sequence level, we prove that uniform allocation is suboptimal and derive variance-minimizing allocation from the first principle, establishing Bernoulli variance as a computable proxy for gradient informativeness. At the token level, we develop gradient-aware advantage modulation grounded in theoretical analysis of gradient magnitude bounds. Our framework compensates for gradient attenuation of high-confidence correct actions while utilizing entropy changes as computable indicators to stabilize excessive update magnitudes. Extensive experiments conducted on a diverse range of mathematical reasoning benchmarks demonstrate consistent improvements over strong RLVR baselines. Our implementation is available at: \href{https://anonymous.4open.science/r/dynamo-680E/README.md}{https://anonymous.4open.science/r/dynamo}.
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