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Steptoe storage vendors cash in on junk platters

Why tech that could extend disk life was rejected

Solving the rotational vibration problem

Packing disk drives closely together can expose each drive to vibrations from its neighbours and so shorten its life. The sealed canister technology developers had to solve this problem, which they attributed to the spinning platters inside the drive, to the drive's rotational vibration (RV).

Sicola's ASA team did lots of development work, and in April 2004 filed its first ISE patent. This design, Wendel believes, did not work because Seagate's people did not understand the source of the rotational vibration. Many, many more Seagate patents followed with one in July 2004, describing a design in which disk drives were fixed in oppositing orientations so as to cancel out RV.

It was not until June 2005 and patent number 11/145, 404, that Seagate designed a technology to cope with the true source of RV, the high-speed acceleration and deceleration of the drive's actuator assemblies during seek operations.

The patent text stated:

The actuator seek torque during acceleration and deceleration imparts rotational vibration stimuli to the enclosure which, in turn, creates an opposite reaction torque. The reaction torque can create rotational vibration interference that adversely affects the data storing and retrieving performance of the device itself, and of adjacent devices in the same support structure. Where a plurality of the devices are grouped together in (an array), the rotational vibration interferences are compounded.

A mass sink is used to deal with this. Wendell says Atrato - he himself - had this problem solved almost 18 months before. His December 2003 patent application, number 60/533,605, stated: "Position drives... such that seek-caused actuator rotational-acceleration vibration causes simultaneous canceling rotational torque."

With the RV problem covered, Seagate completed its ISE development and started trying to sell the technology concept to its OEMs from 2007 or so onwards. But not a single one, in America or Japan, wanted it.

Seagate's misunderstanding of its OEMs' needs

According to Wendel, Seagate's justification for the ISE project was that it was a defence against the commoditisation of Seagate's high-end, enterprise-class, disk business, then Fibre Channel drives but now including SAS drives. These disks would be containerised in a proprietary fashion, and so create a value proposition exclusive to Seagate.

The company postulated that its OEMs (EMC, NetApp, etc) would be willing to give up their array subsystems business, and wanted to do so because they saw their value lay in storage software. Seagate reckoned they'd be happy to use horizontal, scalable building blocks with integrated RAID and other functionality.

"But," Wendel says, "when you look under the covers at where Seagate’s enterprise disk OEMs really make their money (and even now, not one of them wants to admit it), their revenue and profit models were then and still are heavily dependent on selling and maintaining proprietary hardware – including disks and enclosures.

"So, in reality, the Seagate 'bricks' initiative was from the outset extremely disruptive to the 'mainstream market models for making money' among Seagate’s most important OEM customers."

Wendel thinks Seagate's OEM customers rejected the ISE technology because "it threatened to commoditize their entire subsystem value propositions and (probably worse) it dissipated the value of the hardware service and support side of the array vendors' business, a key recurring revenue stream.

"[Seagate's] failure to understand the extent to which ISE would disrupt the very customers they were targeting meant that the product was essentially doomed from the beginning."

Another source close to the situation at the time has talked of discussions, sometimes heated, between Seagate and its OEMs, and of one OEM suggesting it might buy its disk drives elsewhere if Seagate persisted with the ISE technology, but this has not been substantiated elsewhere.

Neither Seagate nor any of the storage array suppliers have corroborated this view of events. One array vendor source said that locking itself in to proprietary Seagate technology was not an attractive proposition when compared to their existing ability to dual or triple source disk drives.

Next page: Seagate's ISE exit

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