Dependency Sensitive Shadow SWIFT

This paper proposes a new commit protocol for real time distributed database systems, dependency sensitive shadow SWIFT (DSS-SWIFT) protocol where the cohort forks off a replica of itself called a shadow, whenever it borrows dirty value of a data item, and if, the created dependency is abort type as compared to creating shadow in all cases of dependency in shadow PROMPT. Also the health factor of cohort is used for permitting to use dirty value of lender rather than health factor of transaction as whole. The performance of DSS-SWIFT is compared with PROMPT, 2SC and SWIFT protocols for both main memory resident and disk resident databases with and without communication delay. Simulation results show that the proposed protocol improves the system performance up to 7% as transaction miss percentage