Abstract: A method for rebuilding a mapping table of a solid state disk includes maintaining the mapping table saved on the buffer memory dynamically, backing up the mapping table regularly, processing user data and a backup mapping table simultaneously for writing to a flash memory array, recording differences between the mapping table and the backup mapping table simultaneously during a backup period, backing up the differences to the flash memory array continuously after the backup mapping table is written to the flash memory array, reading the backup mapping table and backup differences after power is turned on, and rebuilding the backup mapping table according to the backup differences in the buffer memory.

Abstract: A backup method for the mapping table of a solid state disk is provided. When access of a user data and writing of backup data units are processed at the same time, by adjusting a data volume of each of the backup data units and a length of a time lag interval, the data volume of the backup data units to be processed is reduced. More capacity will be available for processing access of the user data. Thus, the access efficiency of the user data is maintained.

Abstract: A solid state drive (SSD) and a method for implementing trim commands of the SSD are provided. The SSD notifies a host that the implementing of the trim commands have been completed when the SSD just modifies deletion flags of lookup table entries based on the received trim commands. Accordingly, the duration for responding to the host is shortened. The SSD implements the trim commands, in the background, on the logical addresses where are marked by the deletion flags, such that the performance of the SSD is improved.

Abstract: The invention is to provide a method for programming and reading a flash memory, storing the last programming page in a block while programming the flash memory, judging the programming times in the cell of the block by means of the last programming page and the order and distribution of the page in the predefined page distribution list of the block while reading the flash memory, and selecting the predefined voltage based on the judged programming times to implement the reading process for raising reading performance.