Thin Provisioning Update

Users are into TP. A survey conducted in July 2007 by SRM vendor MonoSphere revealed that of 249 storage professionals in major verticals who work for "mid-large companies," 78 percent are using, rolling out, or evaluating thin provisioning. (See MonoSphere: Thin Provisioning Risks.)

Seventy-five percent of MonoSphere's respondents involved in thin provisioning cited increased storage hardware utilization as the main advantage they're seeking with this technology. Another 49 percent expect to see easier provisioning with less disruption than they have today; 39 percent cited easier management; and 14 percent expect to get better disk performance.

The biggest drawback perceived by respondents? Running out of storage (71 percent); losing control of management (42 percent); and increasing the complexity of the storage environment (43 percent).

Of those who told MonoSphere they're using thin provisioning, 14 percent are using host-side, volume-based solutions; 64 percent are using array-based products; and 22 percent use filer-based thin provisioning.MonoSphere's axe to grind is its SRM software, the latest version of which it claims manages EMC and NetApp capacity planning and utilization. By extension, MonoSphere claims to support NetApp's FlexVol thin provisioning feature. (See below.)

Speaking of EMC and NetApp... EMC offers thin provisioning for iSCSI and NAS via its Celerra arrays and plans to offer it on CLARiiON and DMX by the first half of next year.

Meanwhile, NetApp claims the FlexVol feature of its ONTAP 7G software enables thin provisioning, even though customers also have the option of buying NetApp software integrated with 3PAR's thin provisioning system.

What's the difference? Depends on whom you ask. (See Tips for Risk-Free Thin Provisioning.)

3PAR's thin provisioning automatically divides up physical disk arrays into "chunklets," which the system doles out in capacity as users request it. While you need 3PAR's hardware to do this, 3PAR claims it's more transparent and automatic than other kinds of thin provisioning, including NetApp's. (See 3PAR, NetApp Join Ranks.)

For its part, NetApp claims its alliance with 3PAR is simply an extension of NetApp capabilities to customers who use 3PAR for back-end block storage. Still, sources point out that NetApp, along with other suppliers like HDS and HP, creates pools of storage from RAID groups, to which users assign LUNs and volumes in the traditional manner, even though the system is faking out the hardware behind the scenes. As actual disk size increases, operators must make adjustments to their volume assignments. Bottom line? Thin provisioning could be more manual.

Intransa adds TP. Intransa has become the last of the big iSCSI SAN players to add thin provisioning, following announcements from LeftHand Networks and EqualLogic. (See Intransa Adds Thin Provisioning and EqualLogic: Thin Is In.)Intransa is offering thin provisioning in a feature called DynaStac, which is a free upgrade for users of its StorStac OS and software suite running with the vendor's 1-, 2-, and 10-Gbit/s systems. The catch? StorStac doesn't run on all of Intransa's systems because it requires more powerful controllers than the ones offered in the vendor's IP3000, IP5500, and IP7500 systems.

"However, customers with existing IntraStor 1GbE systems (IP3000, IP5500, IP7500) can upgrade very inexpensively to StorStac and gain this feature and other features as well," states spokeswoman Kathleen Sullivan.

Intransa IP storage systems are priced from $3,100/Tbyte for systems with 1- and 2-Gbit/s and at $4,500/Tbyte for ones supporting 2- and 10-Gbit/s.

As Intransa and others join the ranks of thin provisioners, it may be important to note that while techniques for implementing the function vary, the type of storage network they're oriented to isn't a factor. "Thin provisioning is not a function of the SAN protocol, it is a function of the storage controller," says one industry analyst, who asked not to be named. "The SAN protocol is irrelevant. Whereas the user value is very relevant."

DataCore does it for free. Another supplier, DataCore, illustrates that hardware need not be a factor at all in thin provisioning. In a promotional campaign announced last week, DataCore is offering a free trial demonstration of its software-based thin provisioning, which works on servers linked to all major vendors' storage arrays. (See DataCore Offers 'Free to Try' Thin Provisioning .) The vendor, which has been ultra-sensitive on its role in the establishment of thin provisioning technology, is keen to show it can deliver it to anyone with a computer, regardless of the kind of storage they have. (See Revisiting Thin Provisioning's 'Firsts'.)