Solid State Drive Performance Analyzer Using Flexible I/O

Abstract: A solid-state drive (SSD) is a data storage device using integrated circuit assemblies as memory to store data persistently. SSD technology uses electronic interfaces compatible with traditional block input/output (I/O) hard disk drives. Solid state disks (SSDs) consisting of NAND flash memory are being widely used in laptops, desktops, and even enterprise servers. SSDs have many advantages over hard disk drives (HDDs) in terms of reliability, performance, durability, and power efficiency. Typically, the internal hardware and software organization varies significantly from SSD to SSD and thus each SSD exhibits different parameters which influence the overall performance. In this paper, we propose a methodology which can extract several essential parameters affecting the performance of SSDs. The target parameters of SSDs considered in this paper are (1)the size of read/write unit, (2) the size of erase unit, (3) the size of read buffer, and (4) the size of write buffer. Obtaining these parameters will allow us to understand the internal architecture of the target SSD better and to get the most performance out of SSD by performing SSD specific optimizations. FIO is an existing tool for I/O performance measurement. It is a tool that will spawn a number of threads or processes doing a particular type of I/O action as specified by the user. FIO has limitations in terms of the number of IO patterns a user can generate. Analyzing performance and understanding behavior of SSDs becomes difficult due to these limitations. We plan to make enhancements to FIO so that a user can generate IO patterns specifically required to exercise various components in an SSD. These will help users characterize SSD performance quicker and precisely.

Keywords: Solid State Drive, Flexible I/O, Hard disk, Nand Flash memory.