iCache: An Intelligent Cache Allocation Strategy for Multitenant in High-Performance Solid-State Disks

Donghua Li, Hui Sun, Xiao Qin

Abstract: Thanks to high-density flash memory and high parallelism, multitenant solid-state drives (MSSDs) have become a popular high-performance storage device for enhancing cache resource utilization and reducing operational costs within these SSDs. The competition for limited cache resources inside the MSSD among multiple tenants, however, can lead to performance interference among the tenants, and prior studies focused on quality of service (QoS) in MSSDs. An efficient caching scheme is crucial for optimizing SSD performance and lifetime. Existing caching schemes aim to shorten response time by the virtue of improved cache hit rates, which offer limited performance improvement as well as low cache resource efficiency. In this article, we propose an intelligent cache allocation scheme named iCache, which employs a long short-term memory (LSTM) model to capture the I/Os access patterns of workloads and dynamically allocates cache resources inside an MSSD according to maximum benefit point (MBP) and optimal allocation point (OAP). The extensive experimental results demonstrate that iCache reduces response time by up to 87%, 24%, and 20% compared against the existing caching schemes—Shared, Justitia, and MLCache, respectively. The empirical study confirms that the new traits of iCache immensely improve system performance by enhancing the cache efficiency of MSSDs and guaranteeing fairness in performance across varying workloads.