Abstract
The cost-per-bit of NAND flash memory has been continuously improved by semiconductor process scaling and multi-leveling technologies (e.g., a 10 nm-node TLC device). However, the decreasing lifetime of NAND flash memory as a side effect of recent advanced technologies is regarded as a main barrier for a wide adoption of NAND flash-based storage systems. In this paper, we propose a new system-level approach, called dynamic program and erase scaling (DPES), for improving the lifetime (particularly, endurance) of NAND flash memory. The DPES approach is based on our key observation that changing the erase voltage as well as the erase time significantly affects the NAND endurance. By slowly erasing a NAND block with a lower erase voltage, we can improve the NAND endurance very effectively. By modifying NAND chips to support multiple write and erase modes with different operation voltages and times, DPES enables a flash software to exploit the new tradeoff relationships between the NAND endurance and erase voltage/speed under dynamic program and erase scaling. We have implemented the first DPES-aware FTL, called autoFTL, which improves the NAND endurance with a negligible degradation in the overall write throughput. Our experimental results using various I/O traces show that autoFTL can improve the maximum number of P/E cycles by 61.2% over an existing DPES-unaware FTL with less than 2.2% decrease in the overall write throughput.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 12th USENIX Conference on File and Storage Technologies, FAST 2014 |
| Publisher | USENIX Association |
| Pages | 61-74 |
| Number of pages | 14 |
| ISBN (Electronic) | 9781931971089 |
| State | Published - 2014 |
| Event | 12th USENIX Conference on File and Storage Technologies, FAST 2014 - Santa Clara, United States Duration: 17 Feb 2014 → 20 Feb 2014 |
Publication series
| Name | Proceedings of the 12th USENIX Conference on File and Storage Technologies, FAST 2014 |
|---|
Conference
| Conference | 12th USENIX Conference on File and Storage Technologies, FAST 2014 |
|---|---|
| Country/Territory | United States |
| City | Santa Clara |
| Period | 17/02/14 → 20/02/14 |
Bibliographical note
Funding Information:We would like to thank Erik Riedel, our shepherd, and anonymous referees for valuable comments that greatly improved our paper. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science, ICT and Future Planning (MSIP) (NRF-2013R1A2A2A01068260). This research was also supported by Next-Generation Information Computing Development Program through NRF funded by MSIP (No. 2010-0020724). The ICT at Seoul National University and IDEC provided research facilities for this study.