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Title: The Design and Implementation of a Capacity-Variant Storage System
We present the design and implementation of a capacityvariant storage system (CVSS) for flash-based solid-state drives (SSDs). CVSS aims to maintain high performance throughout the lifetime of an SSD by allowing storage capacity to gracefully reduce over time, thus preventing fail-slow symptoms. The CVSS comprises three key components: (1) CV-SSD, an SSD that minimizes write amplification and gracefully reduces its exported capacity with age; (2) CV-FS, a log-structured file system for elastic logical partition; and (3) CV-manager, a user-level program that orchestrates system components based on the state of the storage system. We demonstrate the effectiveness of CVSS with synthetic and real workloads, and show its significant improvements in latency, throughput, and lifetime compared to a fixed-capacity storage system. Specifically, under real workloads, CVSS reduces the latency, improves the throughput, and extends the lifetime by 8–53%, 49–316%, and 268–327%, respectively.  more » « less
Award ID(s):
2008453
PAR ID:
10514269
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
USENIX
Date Published:
Journal Name:
22nd USENIX Conference on File and Storage Technologies (FAST ’24)
ISBN:
978-1-939133-38-0
Format(s):
Medium: X
Location:
Santa Clara, CA, USA
Sponsoring Org:
National Science Foundation
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