EMC rolled out its VFCache (“Project Lightning”) server-side flash caching product to great fanfare this week. IBM made a quieter launch, adding a solid-state drive (SSD) caching option to its XIV storage system.
IBM’s XIV Gen3 now includes an option for up to 6 TB of fast-read cache for hot data. IBM offers SSD drives and automatic tiering software as an option for other storage systems, but this is the first SSD option for XIV. XIV systems include one tier – either SATA or high-capacity SAS drives.
Although IBM’s caching option is limited to one of its products, the concept is similar to what EMC is doing throughout its storage array lineup with VFCache. It is speeding read performance for data that needs it while passing writes through to the array.
“It’s like Project Lightning, but in the array,” Silverton Consulting president Ray Lucchesi said. “It’s a similar type of functionality. The differences are IBM is using SSD instead of a PCIe card and it’s at the storage instead of the server. But all the reads go to cache and the writes get destaged to the array.’
The XIV SSD cache is also similar to what NetApp does with its FlashCache, a product that IBM sells through an OEM deal with NetApp. IBM also sells Fusion-io PCIe cards on its servers. EMC has also been selling SSDs in storage arrays since 2008. So we’re seeing that flash is showing up in enterprise storage systems in many ways, and those options will keep expanding.
“As SSDs become more price performant, customers are putting them in for workloads that require quick response times,” said Steve Wojtowecz, IBM’s VP of storage software. ”We’re seeing real-time data retrievals, database lookups, catalog files, and hot data going to SSDs and colder data going to cheaper devices.”
The other big enhancement in XIV Gen3 is the ability to mirror data between current XIV systems and previous versions of the platform. That is most helpful migrating data from older to newer arrays, although IBM is also pushing it as a way to use XIV for disaster recovery.