A Transformation of Repairing Reed-Solomon Codes from Rack-Aware Storage Model to Homogeneous Storage Model
Yumeng Yang, Han Cai, Xiaohu Tang
TL;DR
This work tackles repairing Reed-Solomon codes in rack-aware storage by introducing a universal repair framework that uses good polynomials to place code symbols into racks, thereby transforming rack-aware repairs into equivalent repairs under the homogeneous storage model. The authors connect residue-coefficient representations to short RS codes so that existing homogeneous-model repair schemes can be leveraged for multi-node failures within and across racks. They extend and reinterpret known rack-aware RS constructions and introduce new codes based on three classes of TB14 good polynomials, providing bandwidth analyses and explicit repair procedures. The framework enables parallelizable repair, clarifies when single-rack repairs can achieve optimal cut-set bounds, and opens the path to multi-rack repair optimality questions in rack-aware setups with practical implications for data-center storage efficiency.
Abstract
In this paper, we address the node repair problem of Reed-Solomon (RS) coded distributed storage systems. Specifically, to overcome the challenges of multiple-node failures of RS codes under the rack-aware storage model, we employ good polynomials to guide the placement of the conventional RS codes into racks and then propose a novel repair framework for the resultant rack-aware RS codes, which can transform its repair to that under the homogeneous storage model. As applications of our repair framework, firstly we present the repair scheme of multiple-node failures for some existing constructions, which only have non-trivial solutions for repairing a single-node failure before. Secondly, we deduce several new constructions of rack-aware RS codes supporting the repair of multiple-node failures within a single rack and across multiple racks respectively.
