An Efficient Hot-Cold Data Separation Garbage Collection Algorithm Based on Logical Interval in NAND Flash-Based Consumer Electronics

In NAND flash-based consumer electronics, garbage collection can degrade consumer electronics performance. And the extra page writes caused by garbage collection reduce the lifespan of consumer electronics. Hot-cold data separation has a critical impact on garbage collection. Therefore, inaccurate hot-cold data separation significantly affects garbage collection overhead and the performance of wear leveling. In addition, accurate data separation depends greatly on heat calculation of each page in NAND flash and extra memory is required to record page heat information. In this paper, we propose an efficient and novel hot-cold data separation garbage collection algorithm. The proposed algorithm introduces T-P factor which combines update time and page sequence number to calculate the heat of different logical interval rather than page, thus accurate hot-cold data separation can be achieved. Based on T-P factor, garbage collection strategy is improved accordingly. Experimental results show that the proposed algorithm is superior to existing algorithms in terms of garbage collection overhead, wear leveling and extra memory consumption in NAND flash-based consumer electronics.