Distributed algorithms for multiple mutual exclusion based on Maekawa´s √N algorithm

Summary form only given. The authors have developed algorithms which expand Maekawa´s √N algorithm to handle multiple mutual exclusion (AND-synchronization) problems, in which each node obtains mutually exclusive access to a set of resources rather than to a single resource. It involves suspending a requesting process until it successfully locks several resources simultaneously. Unlike a sequence of requests for (separate) single mutual exclusion, this approach prevents deadlock. Distributed multiple mutual exclusion algorithms can be used in many applications, such as updating a replicated database or as part of a deadlock-free two-phase lock protocol in a distributed environment. In a centralized system, two types of multiple mutual exclusion algorithms exist. One type of primitive (called a PBOTH primitive) prevents starvation, but resource utilization is low. Another type of primitive (called an SP/SV primitive) may cause starvation, but resource utilization is high. The authors have developed both types of distributed algorithms