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Performance of Index trees on Flash Memory

Flash memory can be a viable solution for the future embedded systems. Embedded systems usually carry database as a part of embedded software. It is well known that flash memory is far faster than usual hard disk storages especially for read however it takes much time for flash memory to delete than to read or to write. For a database system, index tree on flash memory has been widely studied for its better performance, but there have been no standard measure for flash memory database performance. In order to find the storage access performance of index trees, we measured index tree access time. We choose B-tree, R-Tree and MR-tree for prominent index trees. We also choose hard disk and flash memory for storage devices. With several indexing profiles having different mixture of insert, search (read) and delete of indices, we measured access time performance with different combination of index tree structure and storage device. We hope our result will work as a basis for flash memory database system design and performance trimming.