GUESSTIMATE: A Programming Model for Collaborative Distributed Systems

We present a new programming model Guesstimate for developing collaborative distributed systems. The model allows atomic, isolated operations that transform a system from consistent state to consistent state, and provides a shared transactional store for a collection of such operations executed by various machines in a distributed system. Guesstimate allows each machine to have a replicated copy (called "current guesstimate") of the state so that operations on shared state can be executed locally without any blocking, while also guaranteeing that eventually all machines agree on the sequence of operations executed. Thus, each operation is executed twice, once at the time of issue when it updates the guesstimated state of the issuing machine, and once when the operation is committed (atomically) to the committed state of all machines. While we expect the results of the two executions of the operation to be identical most of the time in the class of applications we study, it is possible for an operation to succeed the first time when it is executed on the guesstimated state, and fail the second time when it is committed. Guesstimate provides facilities that allow the programmer to deal with this potential discrepancy. This paper presents our programming model, its operational semantics, its realization as an API in C#, and our experience building collaborative distributed applications with this model.

PDF file

In   Proceedings of Programming Language Design and Implementation (PLDI 2010)

Publisher  Association for Computing Machinery, Inc.
Copyright © 2007 by the Association for Computing Machinery, Inc. Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, to republish, to post on servers, or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from Publications Dept, ACM Inc., fax +1 (212) 869-0481, or The definitive version of this paper can be found at ACM’s Digital Library --


> Publications > GUESSTIMATE: A Programming Model for Collaborative Distributed Systems