Enabling the Next Generation of Multi-Region Applications with CockroachDB

Abstract

A database service is required to meet the consistency, performance, and availability goals of modern applications serving a global user-base. Configuring a database deployed across multiple regions such that it fulfils these goals requires significant expertise. In this paper, we describe how CockroachDB makes this easy for developers by providing a high-level declarative syntax that allows expressing data access locality and availability goals through SQL statements. These high-level goals are then mapped to database configuration, replica placement, and data partitioning decisions. We show how all layers of the database, from the SQL Optimizer to Replication, were enhanced to support multi-region workloads. We also describe a new Transaction Management protocol that enables local, strongly consistent reads from any database replica. Finally, the paper includes an extensive evaluation demonstrating that CockroachDB's new declarative SQL syntax for multi-region clusters is easy to use and supports a variety of configuration options with different performance tradeoffs to benefit a variety of workloads. We also show that throughput scales linearly with the number of regions, and the new Transaction Management protocol reduces tail latency by over 10x compared to prior approaches.