Staleness-Learning Rate Scaling Laws for Asynchronous RLHF
- URL: http://arxiv.org/abs/2607.01083v2
- Date: Thu, 02 Jul 2026 05:48:25 GMT
- Title: Staleness-Learning Rate Scaling Laws for Asynchronous RLHF
- Abstract summary: We show that stale rollouts introduce a per-step surrogate-gradient bias of order O(S * eta), where S denotes the maximum rollout lag and eta denotes the learning rate.<n>This explains why the maximum stable learning rate may appear weakly dependent on staleness in the horizon-limited regime.
- Score: 18.98349589222509
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: High-throughput RLHF systems often decouple rollout generation from policy optimization, leading to the use of stale rollouts during learner updates. In this work, we study the effect of such staleness in asynchronous GRPO. We make the behavior policy explicit in the GRPO surrogate objective and distinguish between the surrogate-gradient mapping used by the learner and the true total derivative of a distribution-dependent population objective. Under assumptions of local boundedness, distributional smoothness, and behavior-policy smoothness, we show that stale rollouts introduce a per-step surrogate-gradient bias of order O(S * eta), where S denotes the maximum rollout lag and eta denotes the learning rate. We further derive a conditional collapse-time scaling law: when within-cycle drift remains below a batch-level clipping radius, collapse is governed primarily by cumulative learner drift T * eta; when the stale-rollout constraint is active, stability instead depends explicitly on S * eta. This yields a two-constraint stability condition eta << min{R_batch / (S * G_upd), R_crit / (T * G_upd)}, explaining why the maximum stable learning rate may appear weakly dependent on staleness in the horizon-limited regime.
Related papers
- LC-GRPO: Bridging Train-Inference Gap for Flow-Based GRPO with Langevin Correction [59.32834240526981]
Flow-based generative models are typically sampled by solving a deterministic ordinary differential equation (ODE)<n>Existing GRPO methods for flow models replace the Euler-time ODE with aotropic differential equation (SDE) during training.<n>We introduce LC-GRPO, a flow-based GRPO framework with Langevin correction targeting the marginal distribution at the resulting timestep.
arXiv Detail & Related papers (2026-08-06T04:47:57Z) - RELTA-SGLD: Relative-Growth Localized Taming for Nonconvex Stochastic-Gradient Langevin Learning [10.599439539657785]
We introduce RELTA-SGLD, a taming scheme that stabilizes superlinear-gradient updates while reducing unnecessary suppression of the original learning.<n>A threshold determines where the taming turns on, while a relative-growth principle derived from the one-step Lyapunov condition determines the taming strength.
arXiv Detail & Related papers (2026-07-21T19:43:54Z) - SGD at the Edge of Stability: Stochastic Stabilization with Large Learning Rates [2.104588729923885]
Modern deep learning has been shown to operate at the edge of stability.<n>We provide convergence guarantees for Gradient Descent (SGD) applied to the multiclass cross-entropy loss.<n> Experiments validate our theoretical findings and illustrate the benefits of SGD in the large-stepsize regime.
arXiv Detail & Related papers (2026-06-29T21:32:58Z) - Clipping Bottleneck: Stabilizing RLVR via Stochastic Recovery of Near-Boundary Signals [83.0127582612634]
Near-boundary Rescue (NSR) is a minimal, plug-and-play modification that retains out-of-bound tokens to recover lost signals.<n>NSR substantially improves training stability and delivers consistent gains over strong baselines such as DAPO and GSPO.
arXiv Detail & Related papers (2026-05-21T16:45:31Z) - One-Way Policy Optimization for Self-Evolving LLMs [63.8638342097375]
Reinforcement Learning with Verifiable Rewards (RLVR) has become a promising paradigm for scaling reasoning capabilities of Large Language Models (LLMs)<n>We propose One-Way Policy Optimization (OWPO), a method based on the principle of decoupling optimization direction from update magnitude.<n> Experimental results demonstrate that OWPO outperforms strong baselines, including DAPO, OPD, and MOPD.
arXiv Detail & Related papers (2026-05-21T08:25:27Z) - Recovering Physical Dynamics from Discrete Observations via Intrinsic Differential Consistency [12.266189649117003]
We replace local supervision with a global structural constraint.<n>We train a time-conditioned secant velocity field whose deviation from this property serves two purposes.<n>As a training regularizer, it confines the hypothesis space to flows that compose consistently across temporal scales.
arXiv Detail & Related papers (2026-05-08T20:24:32Z) - Improving Search Agent with One Line of Code [68.58667107354253]
Tool-based Agentic Reinforcement Learning (TARL) has emerged as a promising paradigm for training search agents to interact with external tools.<n>We propose textbfSearch textbfAgent textbfPolicy textbfOptimization (textbfSAPO), which stabilizes training via a conditional token-level KL constraint.
arXiv Detail & Related papers (2026-03-10T04:07:39Z) - VESPO: Variational Sequence-Level Soft Policy Optimization for Stable Off-Policy LLM Training [18.849117699859622]
Training stability is a central challenge in reinforcement learning for large language models.<n>We propose Variational sEquence-level Soft Policy Optimization (VESPO)<n> Experiments on mathematical reasoning benchmarks show that VESPO maintains stable training under staleness ratios up to 64x and fully asynchronous execution.
arXiv Detail & Related papers (2026-02-11T09:48:08Z) - Stability as a Liability:Systematic Breakdown of Linguistic Structure in LLMs [5.96875296117642]
We show that stable parameter trajectories lead stationary solutions to minimize the forward KL divergence to the empirical distribution.<n>We empirically validate this effect using a controlled feedback-based training framework.<n>It indicates that optimization stability and generative expressivity are not inherently aligned, and that stability alone is an insufficient indicator of generative quality.
arXiv Detail & Related papers (2026-01-26T15:34:50Z) - Distributed Stochastic Gradient Descent with Staleness: A Stochastic Delay Differential Equation Based Framework [56.82432591933544]
Distributed gradient descent (SGD) has attracted considerable recent attention due to its potential for scaling computational resources, reducing training time, and helping protect user privacy in machine learning.<n>This paper presents the run time and staleness of distributed SGD based on delay differential equations (SDDEs) and the approximation of gradient arrivals.<n>It is interestingly shown that increasing the number of activated workers does not necessarily accelerate distributed SGD due to staleness.
arXiv Detail & Related papers (2024-06-17T02:56:55Z) - Distributionally Time-Varying Online Stochastic Optimization under
Polyak-{\L}ojasiewicz Condition with Application in Conditional Value-at-Risk
Statistical Learning [9.749745086213215]
We consider a sequence of optimization problems following a time-varying distribution via the lens of online optimization.
We show that the framework can be applied to the Conditional Value-at-Risk (CVaR) learning problem.
arXiv Detail & Related papers (2023-09-18T00:47:08Z) - Fine-Grained Analysis of Stability and Generalization for Stochastic
Gradient Descent [55.85456985750134]
We introduce a new stability measure called on-average model stability, for which we develop novel bounds controlled by the risks of SGD iterates.
This yields generalization bounds depending on the behavior of the best model, and leads to the first-ever-known fast bounds in the low-noise setting.
To our best knowledge, this gives the firstever-known stability and generalization for SGD with even non-differentiable loss functions.
arXiv Detail & Related papers (2020-06-15T06:30:19Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.