Iowa Senatorial Deadlocks

Deadlocks as Runtime Exceptions

Deadlocks are a common type of concurrency bug. When a deadlock occurs, it is difficult to clearly determine whether there is an actual deadlock or if the application is slow or hanging due to a different reason. It is also difficult to establish the cause of the deadlock. In general, developers deal with deadlocks by using analysis tools, introducing application-specific deadlock detection mec...

Deadlocks and Safety Properties

Mutations, Flashbacks and Deadlocks

We generalize the theory of permutations of names to so-called mutations that transform tuples by introducing duplicates and fresh names. The theory of mutations underpins an algorithm for detecting deadlocks (i.e. circular dependencies between resources) in a model defining dependencies – the language for lams. We demonstrate that our algorithm is a decision procedure for so-called linear lams...

Request-Based Gossiping without Deadlocks

By the distributed averaging problem is meant the problem of computing the average value of a set of numbers possessed by the agents in a distributed network using only communication between neighboring agents. Gossiping is a well-known approach to the problem which seeks to iteratively arrive at a solution by allowing each agent to interchange information with at most one neighbor at each iter...

Coffman deadlocks in SCOOP

In this paper we address the deadlock detection problem in the context of SCOOP – an OOprogramming model for concurrency, recently formalized in Maude. We present the integration of a deadlock detection mechanism on top of the aforementioned formalization and analyze how an abstract semantics of SCOOP based on a notion of “may alias expressions” can contribute to improving the deadlock detectio...