HDS Builds Flash Storage to Boost Performance, Endurance

Hitachi Data Systems has developed and launched its own flash storage module for its Virtual Storage Platform (VSP) to meet performance demands of enterprise customers.

The company says its in-house designed flash storage was built from scratch to outperform conventional SSD technology. The company claims its flash storage will deliver better performance, energy efficiency, capacity and lower costs per bit. In addition, HDS says, its controller can improve the endurance of flash memory.

The flash module comes in a rack-optimized form factor and takes advantage of Hitachi's memory controller, which was launched in August as part of its overall flash strategy. In September, the company released its Hitachi Unified Storage VM.

The HDS accelerated flash storage gains some of its advantages through its proprietary form factor, the company says, fitting into an 8U flash chassis that provides up to four times greater density: It can scale from 6.4Tbytes up to 153.6Tbytes of flash storage. Up to four enclosures can be placed in one VSP to exceed 600Tbytes of flash storage. It can be configured in RAID-1, RAID-5 and RAID-6.

For now, the accelerated flash storage will be found in the company's VSP and works with Hitachi Dynamic Tiering to place the most active data on the flash storage. HDS said the new flash module may eventually find its way into other product lines, but it will continue to source SSD from partners for most of its other products.

Ashish Nadkarni, research director of storage systems at IDC, says the company's development of its own flash module and controller stands out from vendors who use commodity flash and make it work in a storage array using software. However, he notes, it's difficult at this point to confirm whether HDS can deliver the speed and performance it touts for the new module. "We don't know what kind of challenges they might face once they start to deploy it," he says.

Henry Baltazar, senior storage analyst at 451 Research, says the recently announced flash controller is just as significant as HDS building its own flash memory module. He says the vast majority of competitors use other vendors' controller technology; HDS updated its VSP firmware when it introduced the controller to boost the number of IOPS. "They realized it doesn't make sense to put high-performance flash into an array if you can't take advantage of it."

That HDS is addressing the endurance issue for flash memory is also notable, says Baltazar. As flash keeps getting cheaper, its reliability has gone down. "That's why the controllers are so important. If you have a controller that's very efficient, you can minimize the number of writes. It's all about that write endurance."

IDC's Nadkarni notes other vendors often avoid the issue of flash memory endurance because they can't sufficiently address it. Hybrid storage providers such as Nimble that incorporate flash into their arrays are still wary of it, he says, hence the hybrid approach--it doesn't put all of the storage eggs in one basket. Hitachi is acknowledging that flash has limitations, says Nadkarni.

The HDS accelerated flash storage is available now for VSP customers; pricing varies depending on configuration.