Stochastic study of real-time transactions success ratio

ABSTRACT

The well-known and accepted criterion for measuring real-time database systems (RTDBSs) performances is to maximize the transactions success ratio. In this paper, we focus on a stochastic study of firm real-time transactions, i.e, transactions which are aborted and discarded as soon as they have missed their deadlines. The results we obtained is the reasonable approximation of this ratio behavior by a probabilistic distribution with defined parameters. To achieve this objective and due to the lack of real data, we have designed a simulator based on components including probabilistic characteristics: a transactions generator and a conflicts generator. The latter is based on data conflicts level. After testing two kinds of concurrency control protocols, a pessimistic and an optimistic one, simulation results have helped us to determine load conditions where a kind of protocol is better than the other.

References

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Index Terms

• Computing methodologies

  • Concurrent computing methodologies

  • Modeling and simulation

    • Model development and analysis

      • Model verification and validation

• Information systems

  • Data management systems

    • Database management system engines

      • Database transaction processing

  • Information retrieval

    • Evaluation of retrieval results

• Mathematics of computing

  • Probability and statistics

    • Stochastic processes

• Theory of computation

  • Models of computation

    • Concurrency

    • Probabilistic computation