R&D: ScaleCache, Scalable Page Cache for Multiple SSDs

ACM Digital Library has published, in EuroSys ’24: Proceedings of the Nineteenth European Conference on Computer Systems proceedings, an article written by Kiet Tuan Pham, Seokjoo Cho, Sangjin Lee, Lan Anh Nguyen, Hyeongi Yeo, Chung-Ang University, Ipoom Jeong, University of Illinois Urbana-Champaign, Sungjin Lee, DGIST, Nam Sung Kim, University of Illinois Urbana-Champaign, and Yongseok Son, Chung-Ang University.

Abstract: “This paper presents a scalable page cache called ScaleCache for improving SSD scalability. Specifically, we first propose a concurrent data structure of page cache based on XArray (ccXArray) to enable access and update the page cache concurrently. Second, we introduce a direct page flush (dflush) which directly flushes pages to storage devices in a parallel and opportunistic manner. We implement ScaleCache with two techniques in the Linux kernel and evaluate it on a 64-core machine with eight NVMe SSDs. Our evaluations show that ScaleCache improves the performance of Linux file systems by up to 6.81× and 4.50× compared with the existing scheme and scalable scheme for multiple SSDs, respectively.“