tailieunhanh - A Case for Flash Memory SSD in Enterprise Database Applications

Sensor queries involve stored data and sensor data, . relations and sequences. We define a sensor query as an acyclic graph of relational and sequence operators. The inputs of a relational operator are base relations or the output of another relational operator; the inputs of a sequence operator are base sequences or the output of another sequence operator, . relations are manipulated using relational operators. | A Case for Flash Memory SSD in Enterprise Database Applications Sang-Won Leet Bongki Moon Chanik Park5 Jae-Myung Kim1 Sang-Woo Kimt tSchool of Information Communications Engr. Sungkyunkwan University SuWon 440-746 Korea wonlee swkim @ 5Samsung Electronics Co. Ltd. San 16 Banwol-Ri Hwasung-City 445-701 Korea Department of Computer Science University of Arizona Tucson AZ 85721 bkmoon@ 1 Altibase Corp. 182-13 Guro-dong Guro-Gu Seoul 152-790 Korea jmkim@ ABSTRACT Due to its superiority such as low access latency low energy consumption light weight and shock resistance the success of flash memory as a storage alternative for mobile computing devices has been steadily expanded into personal computer and enterprise server markets with ever increasing capacity of its storage. However since flash memory exhibits poor performance for small-to-moderate sized writes requested in a random order existing database systems may not be able to take full advantage of flash memory without elaborate flash-aware data structures and algorithms. The objective of this work is to understand the applicability and potential impact that flash memory SSD Solid State Drive has for certain type of storage spaces of a database server where sequential writes and random reads are prevalent. We show empirically that up to more than an order of magnitude improvement can be achieved in transaction processing by replacing magnetic disk with flash memory SSD for transaction log rollback segments and temporary table spaces. Categories and Subject Descriptors H. Information Systems DATABASE MANAGEMENT Physical Design General Terms Design Algorithms Performance Reliability This work was partly supported by the IT R D program of MIC IITA 2006-S-O40-O1 and MIC Korea under iTrC IITA-2008- C1090-0801-0046 . The authors assume all responsibility for the contents of the paper. Permission to make digital or hard copies of all or part of .

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