Experiments in Building Distributed Applications Through Compositional Programming

过去在航空电子和电话等领域构建大规模分布式应用程序的失败惨痛地提醒了我们开发和调试分布式程序的困难。随着应用程序在规模和功能上变得更加雄心勃勃，这些问题只会变得更加复杂。Seuss项目的前提是，这种复杂性可以通过采用更简单的计算模型来管理。Seuss编程模型从大型顺序组件构建分布式应用程序，这些组件通过小而复杂的接口进行交互。该项目有以下目标：(1)开发用于降低这些接口复杂性的概念性工具，(2)重用用标准语言编写的顺序代码片段，(3)通过并发执行各种组件来实现效率。更具体地说，Seuss的并发面向对象编程模型通过允许程序员将分布式应用程序视为顺序程序来推理，从而降低了并发性的复杂性。同时，Seuss允许程序在多个控制线程中执行。最后，Seuss提供了一个逻辑来证明顺序Seuss程序及其多线程执行的等价性。这个项目将允许程序员构建质量上更复杂的分布式应用程序，并保证它们既有效又正确。

Past failures in building large-scale distributed applications in areas such as avionics and telephony are painful reminders of the difficulty of developing and debugging distributed programs. As applications become more ambitious in both scale and functionality, these problems will only be compounded. The Seuss project is based on the premise that this complexity can be managed by adopting a simpler model of computation. The Seuss programming model builds distributed applications from large sequential components which interact through small but complex interfaces. This project has the following goals: (1) to develop conceptual tools for reducing the complexity of these interfaces, (2) to reuse sequential pieces of code written in standard languages, (3) to achieve efficiency by executing the various components concurrently. More specifically, the Seuss model of concurrent object oriented programming reduces the complexity of concurrency by allowing programmers to reason about distributed applications as if they were sequential programs. At the same time, Seuss allows programs to be executed with multiple threads of control. Finally, Seuss provides a logic for proving the equivalence of sequential Seuss programs and their multi-threaded executions. This project will allow programmers to build qualitatively more complex distributed applications with the assurance that they are both efficient and correct.