Improving internal parallelism of solid state drives with selective multi-plane operation

• Published in: Electronics letters Vol. 54; no. 2; pp. 64 - 66
• Main Author: Shin, I
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 25.01.2018
• Subjects: channel level parallelism; chip level parallelism; Circuits and systems; die level parallelism; digital storage; hard disk; internal parallelism; performance evaluation; plane level parallelism; representative server workload; selective multiplane operation; solid state drive; SSD; stability; wasted clean page; wasted clean page; SSD; die level parallelism; performance evaluation; internal parallelism; hard disk; representative server workload; channel level parallelism; selective multiplane operation; digital storage; solid state drive; plane level parallelism; stability; chip level parallelism
• ISSN: 0013-5194; 1350-911X; 1350-911X
• DOI: 10.1049/el.2017.3912

Solid state drives (SSDs) achieve a significantly better performance than hard disks by internally implementing channel level, chip level, and die level parallelism. However, the plane level parallelism has not been sufficiently exploited, because of the constraint that the target pages of the planes must be in the same location. To overcome this constraint, a policy that enforces the multi-plane operation by matching the position of the target pages while wasting clean pages is proposed. However, this policy excessively increases the number of block erasures, which leads to reducing the stability and lifetime of the SSD. To solve this problem, this Letter proposes a policy that determines whether to perform the multi-plane operation considering the number of wasted clean pages. The performance evaluation using representative server workloads shows that the proposed policy improves an average performance by up to 28.82% over the policy that does not perform the multi-plane operation, without significantly increasing the number of block erasures.