Close-up of illuminated server racks, blue lighting.

Mainstream Enterprise

Hard drive manufacturers design drives that will perform well for their largest customers, or sets of customers. This is why “classes” of drives exist.

Design Expectations

The information below is a high-level set of expectations the drive manufacturers have when designing, testing, and selling “Mainstream Enterprise” drives.

Mainstream Enterprise
Power On Hours24 hrs/7 days (8760 POH)
Write / Read Ratio60/40
Block SizesRandom
Seek ProfileRAID Striped w/Parity

Design Details

  • The term “enterprise” to some of the hard drive manufacturers has expanded in definition. Some drives are now being called “enterprise,” or as having “enterprise reliability or features,” that would have never been labeled this just a year or two ago. This is a bit confusing and somewhat aggressive in terms of setting user expectations for reliability.
  • We are calling “Mainstream Enterprise” class drives 7200 rpm, SATA or SAS interface, 1.2M hour MTBF (or higher), fixed shaft spindle, 550 TB/year workload, and of course, tuned for 24/7 usage and using RAID technology.
  • This class of drives has been the choice for most organizations wanting high capacity, adequate throughput performance, and the best reliability/price combination.
  • Performance Enterprise class drives, whether traditional HDD technology or SSD, are much more expensive per unit of capacity than Mainstream Enterprise class drives.

Sealed Drives

To enable next generation capacities, such as 8 TB per drive, HGST has started shipping "sealed" drives filled with helium (versus unsealed drives filled with air). This has allowed higher bit density on the platters and provides other benefits as well. Here is a link for more information: www.hgst.com/science-of-storage/emerging-technologies/helium-technology

Drive Comparison Table

The table below is an excerpt from the HDSTOR Drive Comparison Table, which shows features (or lack thereof) of the different classes of drives, as well as relative performance, reliability, and cost.

Mainstream Enterprise
Production Screening?YES
Rated for 24/7 Use?YES
Fixed Shaft Spindle?YES
RV Feed Forward Sensors?YES
Time Limited Retry Tables?YES
Mainstream Enterprise
Workload RatingEXTREME
Firmware TuningRandom Access/ RAID
Performance CapabilitiesMEDIUM
Reliability RatingsHIGH
CostHIGH