Accelerating Scan Transaction with Node Locking

Transaction processing is widely used for many applications, such as credit card payments or social data analysis. To deal with these applications, scalable concurrency control protocols have been proposed. Modern techniques mainly target SEARCH and UPDATE operations. Unfortunately, the issues of improving the performance of SCAN, which is used for large size of data analysis, and avoiding phantom anomalies have not been addressed. In this paper, we propose a novel protocol for the efficient execution of transactional wide-range SCAN. The proposed protocol, node-locking, acquires locks of the leaf nodes in the tree index during SCAN to prevent phantoms. The proposed protocol avoids deadlocks due to locking by applying the WaitDie protocol to index nodes. On a workload containing SCAN transactions reading 10,000 records, Silo with the proposed protocol shows up to 743 times performance improvement over the original Silo protocol.