DISTRIBUTED CONCURRENCY-CONTROL WITH LOCAL WAIT-DEPTH CONTROL POLICY

Parallel Transaction Processing (TP) systems have great potential to s erve the ever-increasing demands for high transaction processing rate. This potential, however, may not be reached due to the data contentio n and the widely-used two-phase locking (2PL) Concurrency Control (CC) method. In this paper, a distributed locking-based CC policy called L WDC (Local Wait-Depth Control) was proposed for dealing with this prob lem for the shared-nothing parallel TP system. On the basis of the LWD C policy, an algorithm called LWDCk was designed. Using simulation LWD Ck was compared with the 2PL and the base-line Distributed Wait-Depth Limited (DWDL) CC methods. Simulation studies show that the new algori thm offers better system performance than those compared.