Simulation Studies Of The Implementation Of Centralized Two-Phase Locking In DDBMS
نویسندگان
چکیده
One of the most important problems in distributed database systems is the concurrency control. This paper considers algorithms simulating the implementation of centralized two-phase locking (2PL) in distributed database systems and simulation results. It describes specifically the simulations of two-version 2PL and 2PL with integrated timestamp ordering mechanism. In concurrency control method 2PL may take place deadlocks of the transactions. Therefore, in the modeling algorithms described here are integrated algorithms for deadlock avoiding: two-version architecture of database and timestamp ordering strategy “wait-die”. There are also presented, the results of the simulations of these two variants of the 2PL method at different scales of the networks for the transmission of data and at different intensities of inflow transactions. Modeling algorithms are developed by means of the system for simulation modeling GPSS World Personal Version.
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