Does RAID Improve Lifetime of SSD Arrays? Academic Article

abstract

• Parity protection at the system level is typically employed to compose reliable storage systems. However, careful consideration is required when SSD-based systems employ parity protection. First, additional writes are required for parity updates. Second, parity consumes space on the device, which results in write amplification from less efficient garbage collection at higher space utilization. This article analyzes the effectiveness of SSD-based RAID and discusses the potential benefits and drawbacks in terms of reliability. A Markov model is presented to estimate the lifetime of SSD-based RAID systems in different environments. In a small array, our results show that parity protection provides benefit only with considerably low space utilizations and low data access rates. However, in a large system, RAID improves data lifetime even when we take write amplification into account.

authors

• Reddy, Narasimha

published proceedings

• ACM TRANSACTIONS ON STORAGE

altmetric score

• 3

author list (cited authors)

• Moon, S., & Reddy, A.

citation count

• 13

complete list of authors

• Moon, Sangwhan||Reddy, AL Narasimha

publication date

• June 2016

publisher

• Association for Computing Machinery (ACM)  Publisher

published in

• ACM Transactions on Storage  Journal

keywords

• Flash Memory
• Lifetime
• Mttdl
• Raid
• Reliability
• Ssd
• Write Amplification

Digital Object Identifier (DOI)

• 10.1145/2764915

start page

• 1

end page

• 29

volume

• 12

issue

• 3

URL

• http://dx.doi.org/10.1145/2764915