Java 7 Phaser - academia paper

Phasers: a Unified Deadlock-Free Construct for Collective and Point-to-point Synchronization

ABSTRACT
Coordination and synchronization of parallel tasks is a major source of complexity in parallel programming. These constructs take many forms in practice including mutual exclusion in accesses to shared resources, termination detection of child tasks, collective barrier synchronization, and point-to-point synchronization. In this paper, we introduce phasers, a new coordination construct that unifies collective and point-to-point synchronizations. We establish two safety properties for phasers: deadlock-freedom and phaseordering. Performance results obtained from a portable implementation of phasers on three different SMP platforms demonstrate that phasers can deliver superior performance to existing barrier implementations, in addition to the productivity benefits that result from their generality and safety properties.

P.S. From this article - New Java Concurrency Feature: Phasers