A Note on Correctly Gathering Results from JR's Concurrent Invocation Statement

Abstract

JRs concurrent invocation statement (CoStmt, for short) provides a form of collective communication. The thread executing a CoStmt can gather results from each of many invocations. This paper presents a problem that arises in using Java List structures in gathering such results. It presents incorrect and correct attempts at solutions and discusses the tradeoffs, including performance, among the correct solutions.