Highly concurrent directory management in the Galaxy distributed system

An efficient method of consistency control of replicated directories is presented. By taking advantage of special characteristics of directories, the method achieves fast access to directories and high concurrency in updating directory replicas. The algorithm differs from conventional mechanisms for concurrency control of replicated data in two aspects: It does not use global locks or global timestamp orderings. Updating operations can proceed without being in synchronization. The algorithm can survive both node failure and network failure. The directory problem, design objectives and related works are described. The system model and consistency control requirements are defined, and the data structures and algorithm are presented. The fault tolerance and recovery mechanism of the approach are discussed, as is the applicability of the algorithm. The approach is evaluated and compared with other works. The detailed algorithm and consistency proof are given