Performance evaluation of two-phase locking algorithms in a system for distributed databases

In this paper the relationship between average transaction response time and the static degree of interference for four concurrency control algorithms based on two-phase locking is established. In particular the increase in average response time has been measured with respect to the static degree of interference for a given multiprogramming level, database and transaction size. Also the increase in average probability of a lock request conflicting with another one has been measured with respect to the static degree of interference. In addition the average number of aborted transactions has been measureed for each algorithms.