THE STORAGE LANDSCAPE has undergone many changes recently, with EMC, LSI Logic (and, by extension, IBM) and Network...
Appliance (NetApp) all announcing new modular arrays last month. EMC replaced its Clariion CX300, CX500 and CX700 with the new Clariion CX3 family, which includes the CX3 Model 20, CX3 Model 40 and CX3 Model 80. LSI Logic added four new controller models--the 6994, 3994, 3992 Turbo and the 3992, the latter of which IBM will rebrand as its DS4700, replacing the DS4300. Finally, NetApp announced a new high-end family, the FAS6000 line, with a top-end model that scales to 1,008 spindles.
The common thread running through all of these systems is 4Gb/sec Fibre Channel (FC) connectivity, although each vendor supports it in varying degrees. NetApp will offer the FAS6000 in both 4Gb/sec and 2Gb/sec configurations; however, the 4Gb/sec extends out only through the network and to the host. That's the important part anyway, says Patrick Rogers, NetApp's VP of products and partners, "since once the data hits the controller, the transactions get split up anyway."
Conversely, arrays from LSI and EMC feature "end-to-end" 4Gb/sec FC: from the host all the way down to 4Gb/sec disk drives, recently announced by Seagate. LSI's products have been 4Gb/sec-capable since they were introduced last year, says Steve Gardner, director of product marketing at LSI Logic's Engenio Storage Group, but in the absence of other 4Gb/sec components, "the real value of 4Gb/sec was investment protection."
EMC claims to have gone a step further with a brand-new architecture called UltraScale, which is based on its UltraPoint technology introduced last year. The new architecture features improved cache mirroring, point-to-point connections to disk drives and a PCI Express rather than PCI-X bus. Speaking of EMC's competition, Barry Ader, EMC's senior director of Clariion marketing, says, "unless they redesign their ability to have 4Gb/sec speeds within the whole system, we don't believe they will be able to match us in terms of scalability or performance."
Of course, it's difficult to actually measure the performance of EMC's CX3 arrays because the firm declined to cite performance data, even internally generated benchmarks. And whether or not UltraScale truly qualifies as a new architecture is also open to debate. "To me, it's more an enhancement or a refinement of their existing architecture," says Greg Schulz, founder and senior analyst at StorageIO, Stillwater, MN.
That leaves ease of use and scalability. EMC says that based on customer and partner demands, it has improved ease of use with the CX3 family, noting that several components can be serviced by users, including disk drives, power supplies, cooling fans and small form-factor pluggable optical transceivers. Later this year, EMC will allow select users to do their own installations of new Clariions.
Clariion's Virtual LUN and metaLUN software also allow LUN-level data migrations and load balancing without taking the app offline. This should prove useful as customers upgrade from 2Gb/sec to 4Gb/sec disk drives. In addition, the CX3 family offers improved scalability over the previous generation, with up to 120 disk drives on the low-end CX3 Model 20 and 480 drives on the CX3 Model 80, for up to 239TB using low-cost 500GB (7,200 rpm) FC (not SATA) disk drives.
But when it comes to size, NetApp's FAS6000 family blows Clariion away. The new FAS6070 is Symmetrix-like in scale, featuring eight 64-bit processors, up to 1,008 spindles and 64GB of ECC memory. A system of that size will probably be used to consolidate dozens, if not hundreds, of apps, suggests NetApp's Rogers. To that end, NetApp now offers FlexShare, a software option that Rogers says provides "quality-of-service for storage" by setting per-application policies for things like cache utilization and I/O bandwidth. "In the data center environment," he says, "this really matters."