Scalable synchronous queues

We present two new nonblocking and contention-free implementations of synchronous queues, concurrent transfer channels in which producers wait for consumers just as consumers wait for producers. Our implementations extend our previous work in dual queues and dual stacks to effect very high-performance handoff. We present performance results on 16-processor SPARC and 4processor Opteron machines. We compare our algorithms to commonly used alternatives from the literature and from the Java SE 5.0 class java.util.concurrent.SynchronousQueue both directly in synthetic microbenchmarks and indirectly as the core of Java’s ThreadPoolExecutor mechanism (which in turn is the core of many Java server programs). Our new algorithms consistently outperform the Java SE 5.0 SynchronousQueue by factors of three in unfair mode and 14 in fair mode; this translates to factors of two and ten for the ThreadPoolExecutor. Our synchronous queues have been adopted for inclusion in Java 6.

• Type: Conference
• Year: 2006
• Where: PPOPP
• Authors: William N. Scherer III, Doug Lea, Michael L. Scott
• Keywords: Distributed And Parallel Computing, Dual Queues, Java SE, PPOPP 2006, Synchronous Queues