Comparing performance of solid state devices and mechanical disks

Abstract

Abstract-In terms of performance, solid state devices promise to be superior technology to mechanical disks. This study investigates performance of several up-to-date high-end consumer and enterprise Flash solid state devices (SSDs) and relates their performance to that of mechanical disks. For the purpose of this evaluation, the IOZone benchmark is run in single-threaded mode with varying request size and access pattern on an ext3 filesystem mounted on these devices. The price of the measured devices is then used to allow for comparison of price per performance. Measurements presented in this study offer an evaluation of cost-effectiveness of a Flash based SSD storage solution over a range of workloads.In particular, for sequential access pattern the SSDs are up to 10 times faster for reads and up to 5 times faster than the disks. For random reads, the SSDs provide up to 200x performance advantage. For random writes the SSDs provide up to 135x performance advantage. After weighting these numbers against the prices of the tested devices, we can conclude that SSDs are approaching price per performance of magnetic disks for sequential access patterns workloads and are superior technology to magnetic disks for random access patterns.

Evaluating the Energy Efficiency of OLTP Operations

“…A main approach in that direction is the use of Solid State Drives (SSD's) which have been shown to improve performance on typical database operations such as sorting and therefore energy efficiency [4]. Obviously SSDs are faster in such kind of scenarios [10], but there are other tradeoffs as a replacement for HDDs with most obvious the cost per gigabyte (Schall et. all [11], Schröder-Preikschat et.…”

Accelerating enterprise solid-state disks with non-volatile merge caching

“…Storage already represents more than a third of a typical datacenter's direct power consumption [27], as shown in Figure 1, and can be over 70% for storage-heavy installations [33]. The left three drives (highlighted) are solid-state disks (SSDs) [Performance data from Polte et al [24], with average power estimated from datasheets and online reviews. ]…”

“…Polte et al have shown that enterprise-level Flashbased SSDs can provide more than two orders-ofmagnitude improvement in performance over hard disks for random access patterns [24]. We have incorporated published power data on six of the storage devices they tested to estimate the power efficiency (in thousands of I/O operations per second (IOPS) per Watt) as shown in Figure 2.…”

What is the future of disk drives, death or rebirth?

“…As expected, the SSDs are orders of magnitude faster than the traditional disk drives. To better understand the behavior of flash memory based SSDs, Polte et al [2008] performed a thorough investigation about the performance of several high-end consumer and enterprise SSDs, and compared their performance to a few generally available disk drives. They reported that for sequential access pattern, the SSDs are up to 10 times faster for reads and up to 5 times faster for writes than the magnetic disk drives.…”

“…), which can be integrated into the controller of SSDs, have significant impacts on the performance of SSDs. The reader is referred to [Polte et al 2008] for details. Power consumption depends on the characteristics of different storage devices and data access patterns.…”