可扩展全闪存阵列集群的容错擦除代码研究
Exploring Fault-Tolerant Erasure Codes for Scalable All-Flash Array Clusters
摘要：
具有全闪存阵列的大规模系统在许多计算领域变得越来越普遍。为了使这样的系统具有弹性，我们可以采用诸如Reed-Solomon（RS）码的擦除编码作为复制的替代方案，因为擦除编码引起的存储开销比复制低得多。为了了解使用擦除编码对系统性能和其他系统方面（如CPU利用率和网络流量）的影响，我们构建了一个存储集群，该集群由大约100个处理器内核和50多个高性能固态驱动器（SSD）组成，并使用流行的开源分布式并行文件系统（称为Ceph）对集群进行评估。具体来说，我们从以下五个角度分析采用擦除编码的系统的行为，并与另一个使用复制的系统进行比较：（1）存储系统I/O性能;（2）计算和软件开销;（3）I/O放大;（4）存储节点之间的网络流量;（5）物理数据布局对RS编码SSD阵列性能的影响。对于所有这些分析，我们研究了两个代表性的RS配置，使用谷歌文件系统，并将其与三重复制采用一个典型的并行文件系统作为默认的容错机制。最后，我们从集群中收集了96个块级跟踪，并将它们发布到公共领域供其他研究人员使用。
英文摘要：
Large-scale systems with all-flash arrays have become increasingly common in many computing segments. To make such systems resilient, we can adopt erasure coding such as Reed-Solomon (RS) code as an alternative to replication because erasure coding incurs a significantly lower storage overhead than replication. To understand the impact of using erasure coding on the system performance and other system aspects such as CPU utilization and network traffic, we build a storage cluster that consists of approximately 100 processor cores with more than 50 high-performance solid-state drives (SSDs), and evaluate the cluster with a popular open-source distributed parallel file system, called Ceph. Specifically, we analyze the behaviors of a system adopting erasure coding from the following five viewpoints, and compare with those of another system using replication: (1) storage system I/O performance; (2) computing and software overheads; (3) I/O amplification; (4) network traffic among storage nodes, and (5) impact of physical data layout on performance of RS-coded SSD arrays. For all these analyses, we examine two representative RS configurations, used by Google file systems, and compare them with triple replication employed by a typical parallel file system as a default fault tolerance mechanism. Lastly, we collect 96 block-level traces from the cluster and release them to the public domain for the use of other researchers.
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。
