Cold Storage / Archive

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 “Cold Storage and Archive” drives.

  • Power On Hours
  • Write / Read Ratio
  • Block Sizes
  • Seek Profile
  • Cold Storage / Archive
  • 8 hrs/1 days (800 POH)
  • 90/10
  • 2% Random / 98% Sequential

Design Details:

The concept of “cold” storage and “hot” storage has been around quite a while, but now the terms “Cold Storage” and “Archive” are being used by the hard drive manufacturers to label these applications and the innovative drives they are designing to fill the need.  Cold storage or archive, to hard drive manufacturers, simply means digital storage that needs to be kept but rarely accessed.  Customers in this space are asking for lower cost hard drives, since speed, durability and other factors can be sacrificed in order to lower cost.  Capacity and power savings are also key considerations.  The drive manufacturers have responded with several innovations, to date:  SMR (Shingled Magnetic Recording) technology and progressive capacity.  Progressive capacity is an idea WD is using with specific customers where the archive drives they ship to the customer start shipping with higher capacity over time.  For example drives start shipping to the customer at 6TB each but towards the end of the drive program the capacity of each drive is closer to 6.5TB, due to the drive program maturing and yielding an increasing amount of usable capacity per drive.

Here are links from the manufacturers about SMR technology:

Shingled Magnetic Recording
Breaking Areal Density Barriers with Seagate SMR Master TI

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.

  • Production Screening?
  • Rated for 24/7 Use?
  • Fixed Shaft Spindle?
  • RV Feed Forward Sensors?
  • Time Limited Retry Tables?
  • Cold Storage / Archive
  • NO
  • NO
  • NO
  • NO
  • NO
  • Workload Rating
  • Firmware Tuning
  • Performance Capabilities
  • Reliability Ratings
  • Cost
  • Cold Storage / Archive
  • LOW
  • LOW
  • LOW
  • LOW