Abstract
Solid State Disk (SSD) has been highlighted as a next-generation storage device. SSD consists of parallel NAND flash memory. It has much strength, in terms of power consumption, heat, noise and I/O performance compared to a hard disk drive (HDD). However, the implementation of a RAID system to SSDs may reduce lifespan and lower the reliability of SSDs due to frequent update operations of parity disks. Therefore, this paper proposes the block I/O management scheme in a hybrid-RAID system, using the Multi-Level Cell (MLC) and Single-Level Cell (SLC) types of SSDs to improve the reliability, energy efficiency and I/O performance of SSD based RAID system. The proposed method stripes data chunks into MLC disks and parity chunks into SLC disks. It implements erasure code at the device driver level to enhance encoding and decoding performance of a SSD-based hybrid RAID-6 system. Experimental results show that the write performance of the proposed method is 5%, 7%, 15% higher than those of MLC+MLC, HDD+MLC in a RAID-6 system and HPDA in a RAID-4 system, respectively. Read performance of the proposed method is about 7.4%, 43.2%, 38.3% higher than those of MLC+MLC, MLC+HDD in a RAID-6 system and HPDA in a RAID-4 system, respectively.
| Original language | English |
|---|---|
| Pages (from-to) | 487-502 |
| Number of pages | 16 |
| Journal | Information (Japan) |
| Volume | 17 |
| Issue number | 2 |
| State | Published - Feb 2014 |
Keywords
- Erasure code
- Hybrid RAID
- MLC
- SLC
- SSD
- Storage system
