In Proceedings of VLDB ’ 95 : The International Conference on Very Large Databases , Zurich , Switzerland , September 1995 . Value � cognizant Speculative Concurrency Control
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چکیده
We describe SCC kS a Speculative Concurrency Control SCC algorithm that allows a DBMS to use e ciently the extra computing resources avail able in the system to increase the likelihood of timely commitment of transactions Using SCC kS up to k shadow transactions execute speculatively on behalf of a given uncommitted transaction so as to protect against the hazards of blockages and restarts SCC kS allows the system to scale the level of speculation that each transaction is allowed to perform thus providing a straightforward mech anism of trading resources for timeliness Also we describe SCC DC a value cognizant SCC protocol that utilizes deadline and criticalness information to improve timeliness through the controlled defer ment of transaction commitments We present sim ulation results that quantify the performance gains of our protocols compared to other widely used con currency control protocols for real time databases
منابع مشابه
In Proceedings of VLDB ’ 95 : The International Conference on Very Large Databases
We describe SCC-kS, a Speculative Concurrency Control (SCC) algorithm that allows a DBMS to use eeciently the extra computing resources available in the system to increase the likelihood of timely commitment of transactions. Using SCC-kS, up to k shadow transactions execute speculatively on behalf of a given uncommitted transaction so as to protect against the hazards of blockages and restarts....
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