WD has chosen to sit out the 15k RPM market segment. Instead, WD offers a range of products from the NAS-centric IntelliPower WD RED to the 7,200 RPM WD Se and Re for the datacenter. Their subsidiary HGST has a 15k model, but for WDk the Xe is the top of the performance segment. The WD Xe and the Toshiba AL13SE top out at 900 GB, while the Seagate Enterprise Performance v7 has the capacity lead at 1.2TB.
The Xe did not regularly top our charts during testing, but it does have its strengths. The random read performance was superior to the two competing drives, and this high read performance resulted in a good score in our read-heavy webserver testing. Sequential testing was a bright spot for the Xe, and it also excelled at mixed sequential workloads.
The WD Xe unfortunately suffers lower random write performance than its competitors, particularly at lower queue depths. These drives are designed for demanding applications, but performance at the lower queue depths is important in light and bursty workloads. This lower write performance became clear in our write percentage testing where the Xe quickly lost steam as we mixed in a heavier write workload.
The WD Xe consistently provided superior power consumption in comparison to the Toshiba AL13SE and the Seagate Performance v7. This frugal power consumption is matched with a commanding lead in our IOPS to Watts performance measurements. This crucial metric can make a massive difference in TCO over the operational life of the units.
A difference of a 1-1.5 watts in most workloads will equate to massive power and energy savings in a production environment. Hundreds, and sometimes thousands, of drives per deployment add to energy costs quickly. The ongoing power cost will total more than the initial capital expenditure to purchase the drives. With huge power savings over its rivals, the WD Xe has carved itself out quite the niche.
While the difference in performance in most workloads was a handful of IOPS, the tremendous gains in power efficiency will outweigh the performance for many customers. In the majority of production environments, drives are deployed en masse into RAID and parity environments. These groupings of drives can mask small performance differences between drive models.
The WD Xe certainly does not skimp on enterprise-class features. WD has infused the Xe with a healthy dollop of their core IP, including StableTrac, RAFF, NoTouch ramp load technology, and RAID specific TLER. The Xe has been through significant pre-launch testing and has spent an extended period in general availability. The focus on quality leads to a MTBF of 2,000,000 hours and a five-year warranty.
In the enterprise space, measuring the merits of every storage device on performance alone is a foolhardy proposition. Instead, there is a complex mixture of factors that come into play. With advanced tiering and caching systems maximizing the performance tier, power consumption is becoming a larger factor.
PRICING: You can find the Western Digital Xe for sale below. The prices listed are valid at the time of writing but can change at any time. Click the link to see the very latest pricing for the best deal.
United States: The Western Digital Xe (900GB) retails for $350.00 at Amazon.