The Effect of Flashcache and Bcache on I/O Performance

[摘要] Solid state drives (SSDs) provide significant improvements in random I/O performance over traditional rotating SATA and SAS drives. While the cost of SSDs has been steadily declining over the past few years, high density SSDs continue to remain prohibitively expensive when compared to traditional drives. Currently, 1 TB SSDs generally cost more than USD $1,000, while 1 TB SATA drives typically retail for under USD $100. With ever-increasing x86-64 server CPU core counts, and therefore job slot counts, local scratch space density and random I/O performance have become even more important for HEP/NP applications. Flashcache and Bcache are Linux kernel modules which implement caching of SATA/SAS hard drive data on SSDs, effectively allowing one to create hybrid SSD drives using software. In this paper, we discuss our experience with Flashcache and Bcache, and the effects of this software on local scratch storage performance.

[发布机构] Brookhaven National Laboratory, Upton; NY; 11973, United States^1

[效力级别] 计算机科学 [学科分类] 计算机科学（综合）

[关键词] CPU cores;Hard drives;Linux kernel;SATA drives;Solid state drives;Space densities;Storage performance