This paper proposed an efficient spatial Access method, called MDR-Tree (Mbr compression and Delayed write operation based R-Tree), that uses the node compression technique and the delayed write operation technique for flash memory embedded systems. The node compression technique of MDR-Tree increased the utilization of flash memory space by compressing the MBR of spatial data using relative coordinates and MBR size. Moreover, the delayed write operation technique reduced the number of write operations in flash memory by temporarily storing spatial data in the buffer and by reflecting them in flash memory at once instead of reflecting the insert, update and delete of spatial data in flash memory for each operation. Especially, the utilization of buffer space was enhanced by preventing the redundant storage of the same spatial data in the buffer.
Real-time garbage collection for flash-memory storage systems of real-time embedded systems
