Dual Actuator drives: An interesting trend

The future of spinning disc is still in question. For the past couple years, I’ve talked quite extensively about the value of Solid-State storage media supplanting spinning disc in a variety of categories. I’ve pretty much relegated spinning disc to long term archive, and very low transaction categories. The problems I’ve outlined have been those key benefits of durability, and IO speed. The MTBF on spinning discs, by virtue of the fact that the media is a moving architecture can lend itself to failure because moving parts are generally more vulnerable. But the balance and development of mechanisms has made that kind of failure far more rare. Also, speed differentials between the solid-state, particularly with newer connectivity options (NVMe, for example) and spinning disc are profound. But do we need that kind of speed in all categories of storage? I’m just not so sure.

Along comes the advent of “Dual-Actuator Drives.” These discs essentially double the read/write time on the disc itself, because now the head mechanism is doubled. With two actuator arms reading and writing to that media, they seem to have accomplished a key differentiator.

In the history of spinning disc, the faster the disc spins, the better the IO. This is how it’s been. The thing is, that a 15,000 RPM disc is the theoretical limit. Beyond that the imperfections can cause the disc to break up within the casing. With the advent of a dual-head mechanism, the reliance on the speed of the spinning of the disc has lessened. The magnetic read/write mechanism being doubled, and handling via logic, these discs promise to extend the viability of spinning media, giving it even more viability beyond that of long term archive, and allowing for speeds to be achieved that spinning disc hadn’t yet been able to achieve.


Up until this point, and probably since last year, the Seagate and Toshiba brands have launched products, but at #SFD18, we were treated to a presentation by Western Digital, talking about their many products, and how they’ve added so dramatically to their lines. The acquisition of Tegile, a storage array company, I’ve long admired, their development of 3D Nand (not to be confused with 3D Crosspoint) have achieved quite new excitement within the organization.

Their release of a dual-actuated drive technology in their core spinning disc category to me has been actually quite interesting. For the longest time, I’ve been confident that we’d never see a future for spinning disc, but there is definitely new life here. I will once again say that I’m thrilled at the growth in many categories for Western Digital. This new energy presented by WD at this event really is exciting.




3 thoughts on “Dual Actuator drives: An interesting trend

  1. Surely it will half the access time not double?

    The image is a bit misleading as it it doesn’t actually show dual actuators

    I can remember Richie Lary talking about testing samples of 22K rpm disks and dual actuators back around the turn of the century!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.