Accelerated Over-Relaxation Heavy-Ball Method: Achieving Global Accelerated Convergence with Broad Generalization
Jingrong Wei, Long Chen
TL;DR
The paper addresses achieving global accelerated convergence for smooth strongly convex optimization and extends this capability to composite and saddle-point problems. It introduces the Accelerated Over-Relaxation Heavy-Ball (AOR-HB) method, derived from discretizing a two-dimensional accelerated flow with an over-relaxation in the gradient term, and proves a strong Lyapunov property that yields global accelerated linear convergence with optimal iteration complexity $\mathcal{O}(\sqrt{\kappa}\,|\log\varepsilon|)$. The authors further extend AOR-HB to composite convex minimization and to a class of bilinear saddle-point problems via AOR-HB-saddle, providing convergence guarantees and practical single-loop implementations. Numerical results across smooth, composite, non-convex, and saddle-point problems illustrate robust acceleration and competitive performance relative to established first-order methods. Overall, AOR-HB offers broad generalization, conceptual clarity, and a pathway to generalize acceleration techniques beyond traditional convex settings.
Abstract
The heavy-ball momentum method accelerates gradient descent with a momentum term but lacks accelerated convergence for general smooth strongly convex problems. This work introduces the Accelerated Over-Relaxation Heavy-Ball (AOR-HB) method, the first variant with provable global and accelerated convergence for such problems. AOR-HB closes a long-standing theoretical gap, extends to composite convex optimization and min-max problems, and achieves optimal complexity bounds. It offers three key advantages: (1) broad generalization ability, (2) potential to reshape acceleration techniques, and (3) conceptual clarity and elegance compared to existing methods.
