Are SSDs an invasive species?

A head assembly on a Seagate disk drive by Robert Scoble (cc) (from flickr)

A head assembly on a Seagate disk drive by Robert Scoble (cc) (from flickr)

I was reading about pythons becoming an invasive species in the Florida Everglades and that brought to mind SSDs.  The current ecological niche in data storage has rotating media as the most prolific predator with tape going on the endangered species list in many locales.

So where does SSD enter into the picture.  We have written before on SSD shipments start to take off but that was looking at the numbers from another direction. Given recent announcements it appears that in the enterprise, SSDs seem to be taking over the place formerly held by 15Krpm disk devices.  These were formerly the highest performers and most costly storage around.  But today, SSDs, as a class of storage, are easily the most costly storage and have the highest performance currently available.

The data

Seagate announced yesterday that they had shipped almost 50M disk drives last quarter up 8% from the prior quarter or ~96M drives over the past 6 months.  Now Seagate is not the only enterprise disk provider (Hitachi, Western Digital and others also supply this market) but they probably have the lion’s share.  Nonetheless, Seagate did mention that the last quarter was supply constrained and believed that the total addressible market was 160-165M disk drives.  That puts Seagate’s market share (in unit volume) at ~31% and at that rate the last 6 months total disk drive production should have been ~312M units.

In contrast, IDC reports that SSD shipments last year totaled 11m units. In both the disk and SSD cases we are not just talking enterprise class devices, the numbers include PC storage as well.  If we divide this number in half we have a comparable number of 5.5M SSDs for the last 6 months, giving SSDs less than a 2% market share (in units).

Back to the ecosystem.  In the enterprise, there are 15Krpm disks, 10Krpm disks and 7.2Krpm rotating media disks.  As speed goes down, capacity goes up.  In Seagate’s last annual report they stated that approximately 10% of the drives they manufactured were shipped to the enterprise.  Given that rate, of the 312M drives, maybe 31M were enterprise class (this probably overstates the number but usable as an upper bound).

As for SSDs, in the IDC report cited above, they mentioned two primary markets the PC and enterprise markets for SSD penetration.  In that same Seagate annual report, they said their desktop and mobile markets were around 80% of disk drives shipped.  If we use that proportion for SSDs that would say that of the 5.5M units shipped last half year, 4.4 were in the PC space and 1.1M were for the enterprise.  Given that, it would state that the enterprise class SSDs represent ~3.4% of the enterprise class disk drives shipped.  This is over 10X more than my prior estimate of SSDs being (<0.2%) of enterprise disk drives.  Reality probably lies somewhere between these two estimates.

I wrote a research report a while back which predicted that SSDs would never take off in the enterprise, I was certainly wrong then.  If these numbers are correct, capturing 10% of the enterprise disk market in little under 2 years can only mean that high-end, 15Krpm drives are losing ground faster than anticipated.  Which brings up the analogy of the invasive species.  SSDs seem to be winning a significant beach head in the enterprise market.

In the mean time, drive vendors are fighting back by moving from the 3.5″ to 2.5″ form factor, offering both 15K and 10K rpm drives.   This probably means that the 15Krpm 3.5″ drive’s days are numbered.

I made another prediction almost a decade ago that 2.5″ drives would take over the enterprise around 2005 – wrong again, but only by about 5 years or so. I got to stop making predictions, …