Formalization and correctness of a concurrent linear hash structure algorithm using nested transactions and I/O automata

摘要

In this paper, we formalize and prove the correctness of a nested transaction version of the concurrency control algorithm using a linear hash structure. Nested transactions allow increased parallel execution of transactions, and handle transaction aborts in our system. We present our nested transaction model in a linear hash structure envi- ronment using a well-known I/O automaton model. We have modeled both the buckets and the transactions as I/O automata. In our algorithm, the locks have been considered at both key and vertex level. These locks have been im- plemented in a nested transaction environment using Moss's two phase locking algorithm and the locking protocols of the linear hash structure algorithm with a lock coupling technique. We have proved that our linear hash structure algorithm in a nested transaction environment is ‘serially correct'. We have discussed briefly the client server archi- tecture for the implementation of our system.