MODERATE CONCURRENCY CONTROL IN DISTRIBUTED OBJECT SYSTEMS
Kenichi Watanabe, Yousuke Sugiyama, T. Enokido, Makoto Takizawa · Journal of Interconnection Networks · 2004
Objects are concurrently manipulated only through methods issued by multiple transactions in object-based systems. We first extend traditional read and write lock modes to methods on objects. We newly introduce availability and exclusion types of conflicting relations among methods. Then, we define a partially ordered relation on lock modes showing which modes are stronger than others. We newly propose a moderate concurrency control algorithm. Before manipulating an object through a method, the object is locked in a weaker mode than an intrinsic mode of the method. Then, the lock mode is escalated to the method mode. The weaker the initial mode is, the more concurrency is obtained but the more frequently deadlock occurs.