A SIMULATION-MODEL FOR THE PRIMARY COPY STRATEGY IN DISTRIBUTED INGRES

In distributed INGRES, the primary copy strategy based on two-phase lo cking is used to solve the concurrency control (cc) problem. To observ e the behaviors of the transactions in distributed INGRES, a simulatio n model is proposed and a simulation is conducted in this paper. Furth ermore, to observe how the primary copy sites for fragments influence the performance of distributed INGRES, we derive a method to select th e primary copy sites such that the system has shorter average processi ng time per transaction, higher throughput, and fewer deadlocks. The e xperimental results obtained from the simulation show that the primary copy sites selected by the method generate the best results under low conflict ratio or long inter-arrival rime. (C) 1998 Elsevier Science Inc. All rights reserved.