Specification and constant RMR algorithm for phase-fair reader-writer lock

Abstract

Brandenburg and Anderson [1,2] recently introduced a phase-fair readers/writers lock [1,2], where read and write phases alternate: when the writer leaves the CS, any waiting reader will enter the CS before the next writer enters the CS; similarly, if a reader is in the CS and a writer is waiting, any new reader that now enters the Try section will not enter the CS before some writer enters the CS. Thus, neither class of processes-readers or writer-has priority over the others, and no process starves. Brandenburg and Anderson [1,2] informally specify a phase fair lock and present an algorithm to implement it with O(n) remote memory reference complexity (RMR), where n is the number of processes in the system. In this work we give a rigorous specification of a phase fair lock and present an algorithm that implements it with O(1) RMR complexity. © 2011 Springer-Verlag Berlin Heidelberg.