Introduction

The migration to slimmer servers has touched off an intense need to provide the most performance in the smallest package possible for all components deployed into the datacenter environment. Toshiba MK01GRRB/R hard disk drives provide the ability to place a relatively high amount of storage, up to 300GB, into a small 2.5" form factor.

We are witnessing a revolution in server design, with the focus changing to power sipping drives that deliver high performance. Many small form-factor server racks offer a limited number of drive bays, so the full utilization of the direct attached storage is necessary.

We originally tested the MK01GRRB/R as a single drive, and its excellent performance led us to choose this as the HDD to utilize as our base array for several caching solutions we are currently testing.

The MK01GRRB/R operates at 15,000 RPM, delivering a good combination of speed, capacity and agility. This series of HDDs also includes models that have integrated encryption that does not adversely affect performance.

The Toshiba HDDs come in a 2.5" form factor with a 15mm Z-Height. These HDDs also feature a 6Gb/s SAS connection to provide enterprise class features such as multipath and failover. SAS is known for its High Availability features and is a great fit for enterprise applications.

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These HDDs are typically deployed in parity RAID configurations in large numbers. Performance variability from HDDs can lead to uneven performance in RAID scenarios, as the configuration is constrained to the slowest I/O from any device. Groups of HDDs that suffer poor maximum latency will effectively function at the maximum latency received from any individual drive.

This places the focus on consistent performance for better performance in RAID arrays. Today we will test eight Toshiba MK01GRRB/R drives in a RAID 5 configuration with arrays of 3, 5 and 8 drives. This testing will focus on spotting performance variability and the scaling of the solution employed.