A Garbage Collection Method Using Block-level Buffer in Flash Memory

摘要

As the usage of mobile devices and mobile phones has rapidly increased, flash memory has been considered as the next-generation storage systems to replace the hard-disk because it has some advantages such as faster access speed, lightweight, low power consumption, small size and shock resistance. As a result, various researches have been studied to improve its buffer usage efficiency. In this paper, we propose a novel garbage collection scheme, called the block-level buffer aware garbage collection. The proposed scheme not only merges the data blocks and the corresponding log block, but also searches for the block-level buffer to find the corresponding buffer blocks. The proposed method reduces unnecessary potential page copying operations and block erasure operations. Therefore, the performance of flash memory is improved and the lifetime of flash memory is also prolonged. Compared with the existing garbage collection methods, our experimental results show that the proposed method reduces the block erase operations and page migration operations when collecting the same amount of garbage.