A Comparison of Two Distributed Systems: Amoeba and Sprite

This paper compares two distributed operating systems, Amoeba and Sprite. Although the systems share many goals, they diverged on two philosophical grounds: whether to emphasize a distributed computing model or traditional UNIX-style applications, and whether to use a workstation-centered model of computation or a combination of terminals and a shared processor pool. Many of the most prominent features of the systems (both positive and negative) follow from the philosophical differences. For example, Amoeba provides a high-performance user-level IPC mechanism, while Sprite's RPC mechanism is only available for kernel use; Sprite's file access performance benefits from client-level caching, while Amoeba This work was supported in part by the Netherlands Organization for Scientific Research (N.W.O.) under grant NF 62-334. @ Computíng Systems, Vol. 4 . No. 4 . Fall 1991 353 caches files only on servers; and Sprite uses a process migration model to share compute power, while Amoeba uses a centralized server to allocate processors and distribute load automatically.