I’ve been waiting a long time for the transition to 2.5″ drives. Now it appears that the wait is over and it is truly underway. The dynamics aren’t what I expected.

The impetus: installing a new WD 300 GB VelociRaptor 10k drive in my Mac Pro. It is a 3.5″ heatsink wrapped around a tiny 10k 2.5″ drive. I’ll be running some tests on it shortly.

Fujitsu’s 2.5″ bet
Fujitsu’s Don Jeanette tried to brief me last week on their new drives, but I was more interested in their experience with the 2 form factors. Although the company is off the radar in most disk discussions – stealth marketing never dies! – I remember back in the ’80s when their 9″ Eagle was the drive to beat.

Fujitsu exited the consumer 3.5″ market in 2001, but still offer 3.5″ enterprise drives along with 2.5″ small form factor (SFF) enterprise and consumer drives. Now half their enterprise drives are SFF, a market where they are 2nd only to Seagate.

The consumer SFF
Notebooks dominate consumer SFF uptake, but as I look at my huge Mac Pro enclosure, it is obvious that smaller tower systems would also benefit. In the space used for 4 3.5″ drives, Apple could plug 20 SFF drives – and increase capacity by 50%.

With efficient many core CPUs, SFF drives, higher density DRAM, Intel’s new QuickPath (pdf) architecture, smaller fans and plenums, a much more powerful system than an 8-core Mac Pro could be built into a box 2/3rds the size. Hey, and lose the power-hungry FB-DIMMs while you’re at it!

The enterprise SFF
Consumers drive volume, but the enterprise drives margin. I assume Xiotech is well along on designing enterprise-ready drive shelves.

The interconnect issues must be interesting: internal SAS switches or cheaper high fan-out configurations? No issues we didn’t see in the move from 5.25″ to 3.5″, but it is a chance for a clean sheet design.

I’d welcome a call from Xyratex to discuss the topic.

The Seagate rumor
I’ve heard from a couple of sources that Seagate is currently designing its last family of 3.5″ drives. They’ve had good success with the Savvio SFF enterprise drives, so it is now up to the OEMs to make the move.

The StorageMojo take
With Fujitsu as a credible 2nd source, OEMs have no reason not to start down the SFF path. While the nearline guys will be the last to move off 3.5″ drives, the combination of more spindles/IOPS/bandwidth per U/$/watt should be persuasive – especially against surging flash drives.

The revenue crossover could be 2010, while Fujitsu’s Jeanette predicted unit crossover in 2011. With 6 SFF vendors competing for the business the pace of innovation should accelerate – to the lasting benefit of all storage consumers.

Update: Belatedly came across an article from the October 3rd WSJ. The money points:

CHIBA, Japan — Japanese electronics company Toshiba Corp. would be interested in Fujitsu Ltd.’s hard-disk-drive business, if approached, an executive said Thursday. . . .

The Fujitsu spokesman declined to comment on whether it is in talks with Toshiba.

Fujitsu expects its hard-disk-drive operation will break-even or post a slight loss on estimated revenue of 370 billion yen ($3.49 billion) for its fiscal year ending March 2009.

While Toshiba won’t disclose the performance of its hard-disk-drive business, Mr. Izumi estimates it could generate about 10 billion yen in operating profit and 360 billion yen in revenue for the current fiscal year.

End update.

Update II: Pete Steege of Seagate commented with a couple of links to his blog on the topic. Following those I found some more info on 2.5″ arrays that I’d missed.

• Xyratex the enclosure maker (not, oops, Xiotech – sorry) has a 2.5″ enclosure, the OneStore SP1224s, for sale.
• The Dell MD1120 is a 2.5″ RAID subsystem that appears to be based on the Xyratex enclosure.

End update II.

Courteous comments welcome, of course.