Improvements in Shadow SWIFT using Selective Commit and Delayed Creation of Shadows

In normal shadow SWIFT commit protocol shadow of all the borrower transactions which satisfy a given criteria are created when the lock manager processes the request. This creates heavy overhead on the system and degrades its performance. In this paper, we have presented a new method of handling the requests by the borrower transactions. We create the shadow only when the borrower aborts due to abort of lender and can complete its execution in the remaining time. Further, the shadow uses the work already done by borrower transaction .We also propose the use of selective commit depending on Lender’s commitment. Thus it prevents any overhead associated with the maintenance of the shadow as was the case in earlier shadow based protocols.