CSR: Small: Client-Centric Consistency

存储系统提供的隔离保证规范了并发执行的多个事务如何正确地读取和写入数据。同样，当在地理位置不同的位置(如Facebook和Twitter)复制和更新数据时，一致性保证指定哪些数据对访问不同副本的客户端可见。该项目将开发一种新的以程序员为中心的模型，以便在单个框架中严格表达地理复制存储系统提供的隔离和一致性保证。然后，它将利用新的模式，寻求更有效的方式来落实这些保证。该项目将沿着三个方向推进。首先，它将寻求将隔离和一致性保证表示为应用程序可以观察的状态的属性，而不是依赖于低级读/写操作的不可见历史。其次，它将寻求克服当前出现的可扩展性瓶颈，这些瓶颈出现在速度慢或有故障的服务器上，到目前为止，这些瓶颈扼杀了行业部署因果一致的地理复制数据存储的兴趣。第三，它将利用其对一致性和隔离的统一处理，首次在可扩展的一致性数据存储上支持通用读/写事务。该项目直接满足了研究和行业对大规模、事务性分布式系统日益增长的兴趣。通过直面可伸缩性的关键障碍，它将有助于在二十年来对因果一致性的学术研究取得工业成果。此外，通过建立讨论一致性和孤立性的共同语言，这将使系统和数据库研究界之间能够进行更富有成效的交流，因为它们的主要重点分别是一致性和孤立性，它们经常互相谈论。该项目将理论研究和实验研究紧密结合在一起，非常适合向研究生和本科生介绍研究，并将提供一种新的方法，在分布式计算中教授研究生和本科课程的一致性和孤立性。项目成果(发表的论文、演示文稿和用于展示项目结果的软件和工作量的存储库)将在Address http://www.cs.utexas.edu/users/lorenzo/projects/CCC/，上下载，这些成果将保存五年。

The isolation guarantees offered by a storage system regulate how multiple transactions executing concurrently read and write data correctly. Similarly, when data is replicated and updated at geographically-distinct locations (as do Facebook and Twitter), consistency guarantees specify which data is visible to clients that access different replicas. This project will develop a new programmer-centric model for expressing rigorously, in a single framework, the isolation and consistency guarantees offered by geo-replicated storage systems. It will then leverage the new model to seek more efficient ways to implement these guarantees.The project will proceed along three thrusts. First, it will seek to express isolation and consistency guarantees as properties of states that applications can observe, instead of relying on invisible histories of low-level read/write operations. Second, it will seek to overcome the current scalability bottlenecks that arise with slow or faulty servers, which have, to date, stifled industry's interest in deploying causally-consistent geo-replicated data stores. Third, it will leverage its unified treatment of consistency and isolation to support, for the first time, generic read/write transactions on top of a scalable consistent data store.The project directly addresses the growing interest in both research and industry towards large-scale, transactional distributed systems. By confronting key obstacles to scalability, it will contribute to bring to industrial fruition over two decades of academic research on causal consistency. Further, by establishing a common language to discuss consistency and isolation, it will enable more fruitful exchanges between the systems and database research communities, who, because of their primary focus on, respectively, consistency and isolation, have often been talking past each other. The project, with its tight integration of both theoretical and experimental research, is ideally suited to introducing graduate and undergraduate students to research, and will offer a new approach to teaching consistency and isolation in graduate and undergraduate courses in distributed computing.The project outcomes (papers published, presentations, and a repository of the software and workloads used to demonstrate the results of the project) will be made available for download at the address http://www.cs.utexas.edu/users/lorenzo/projects/CCC/, where they will be kept for five years.