使用Raft和混合逻辑时钟的会话保证
Session Guarantees with Raft and Hybrid Logical Clocks
摘要：
最终一致性是地理复制数据存储的流行一致性模型。尽管最终一致性提供了高性能和可用性，但它可能导致异常，使应用程序开发人员的编程变得复杂。与更强的一致性模型相比，会话保证可以消除其中一些异常，同时导致更低的开销。在本文中，我们提供了一个协议，为NuKV提供会话保证，NuKV是eBay上为具有非常高的可用性和性能要求的服务开发的键值存储。NuKV依赖于Raft协议在数据中心内进行复制，并使用最终一致性在数据中心之间进行复制。我们提供了传统的会话保证的修改版本，以避免在系统中有大量的分区的减速级联的问题。我们还使用混合逻辑时钟来消除延迟写操作的需要，以满足会话保证。我们的实验表明，我们的协议提供了一个可以忽略不计的开销相比，最终的一致性会话保证。
英文摘要：
Eventual consistency is a popular consistency model for geo-replicated data stores. Although eventual consistency provides high performance and availability, it can cause anomalies that make programming complex for application developers. Session guarantees can remove some of these anomalies while causing much lower overhead compared with stronger consistency models. In this paper, we provide a protocol for providing session guarantees for NuKV, a key-value store developed for services with very high availability and performance requirements at eBay. NuKV relies on the Raft protocol for replication inside datacenters, and uses eventual consistency for replication among datacenters. We provide modified versions of conventional session guarantees to avoid the problem of slowdown cascades in systems with large numbers of partitions. We also use Hybrid Logical Clocks to eliminate the need for delaying write operations to satisfy session guarantees. Our experiments show that our protocol provides session guarantees with a negligible overhead when compared with eventual consistency.
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。
