arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2111.07884cs.DCcs.ITmath.IT
收藏

无线分布式存储系统中多个部分故障的功能广播修复

Functional Broadcast Repair of Multiple Partial Failures in Wireless Distributed Storage Systems

Nitish Mital, Katina Kralevska, Cong Ling, Deniz Gunduz

摘要:

考虑一个具有$n$节点的分布式存储系统,用户可以从任意$k$节点恢复存储的文件,并研究了部分失效的$r$节点的修复问题.我们考虑\textit{broadcast repair},即$d$幸存节点在无差错的无线信道上向正在修复的$r$节点发送广播消息,然后使用这些消息以及故障节点的本地存储器中的幸存数据来恢复丢失的内容。首先,我们推导出的存储容量和修复带宽的部分修复多个故障节点之间的权衡,基于信息流图的割集界。它示出,利用广播性质的无线介质和幸存的内容在部分故障节点的修复带宽显着降低每个节点。然后,我们列出了一组不变的条件是足够的功能修复代码是可行的。我们进一步提出了一个计划的功能修复多个失败的节点,满足不变条件的概率很高,其扩展到部分故障的修复。当$k$可被$r$整除时,该方案的性能满足折衷曲线上所有点的割集界,同时采用线性子分组,这是分布式存储码设计中的一个重要实际考虑因素。与通常用于故障节点功能修复的随机线性码不同,该修复方案具有较低的开销、较低的输入输出代价和修复过程中较低的计算复杂性.

英文摘要:

We consider a distributed storage system with $n$ nodes, where a user can recover the stored file from any $k$ nodes, and study the problem of repairing $r$ partially failed nodes. We consider \textit{broadcast repair}, that is, $d$ surviving nodes transmit broadcast messages on an error-free wireless channel to the $r$ nodes being repaired, which are then used, together with the surviving data in the local memories of the failed nodes, to recover the lost content. First, we derive the trade-off between the storage capacity and the repair bandwidth for partial repair of multiple failed nodes, based on the cut-set bound for information flow graphs. It is shown that utilizing the broadcast nature of the wireless medium and the surviving contents at the partially failed nodes reduces the repair bandwidth per node significantly. Then, we list a set of invariant conditions that are sufficient for a functional repair code to be feasible. We further propose a scheme for functional repair of multiple failed nodes that satisfies the invariant conditions with high probability, and its extension to the repair of partial failures. The performance of the proposed scheme meets the cut-set bound on all the points on the trade-off curve for all admissible parameters when $k$ is divisible by $r$, while employing linear subpacketization, which is an important practical consideration in the design of distributed storage codes. Unlike random linear codes, which are conventionally used for functional repair of failed nodes, the proposed repair scheme has lower overhead, lower input-output cost, and lower computational complexity during repair.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑