SAN FRANCISCO -- EMC Corp. emphasized its commitment to flash across all levels of storage this week at VMworld, upgrading its VFCache PCIe card-based flash caching product with inline dedupe and demonstrating its "Project X" all-flash array, which
EMC VFCache 1.5 included no major enhancements but had several improvements over the first version that launched in February. Besides adding inline deduplication for cached data, VFCache now supports VMware vMotion and the ability to use multiple cards in one server. EMC also added support for Micron 700 GB capacity single-level cell (SLC) PCIe cards -- more than twice the top capacity supported in the first VFCache, and an LSI Nytro WarpDrive PCIe flash mezzanine card for Cisco UCS B-series blades.
VFCache 1.5 comes a week after EMC rival NetApp launched its Flash Accel flash caching software that works with any PCIe card. VFCache supports only Micron and LSI cards. NetApp's Flash Accel supports vMotion, but not dedupe.
"EMC believes that flash could be and should be put in a variety of places," said Barry Ader, EMC's senior director of product management for flash products. "There is no 'This is the only place you can deploy flash.' Flash should go everywhere."
Ader said EMC is using the deduplication algorithm from its Avamar host-based backup software for VFCache. Inline dedupe makes the effective cache size larger than the physical size, improving the cost per gigabyte. The larger effective cache size requires less writes to the card, extending the life of the flash.
However, the dedupe ratio for cached data is relatively small compared to backup or even primary data because cached data has little duplication. EMC cites a 20% dedupe gain as reasonable for Microsoft Exchange, which would turn a 300 GB physical cache into a 360 GB effective cache.
Interoperability with vMotion lets customers perform maintenance on a server with VFCache without downtime. They can vMotion an application from one virtual machine to another, do maintenance and then vMotion the application back. Previously, customers had to stop running VFCache if they took a server down. "Some customers do vMotion all the time, some might do it once a month," Ader said.
EMC VFCache also now supports NetApp and IBM storage systems along with EMC storage arrays.
Ray Lucchesi, president of Broomfield, Colo.-based Silverton Consulting Inc., said it's no surprise that EMC added dedupe to VFCache considering it is already a leader in the dedupe market with its Avamar and Data Domain backup dedupe. "EMC has more dedupe technology than anybody," he said.
Lucchesi said EMC's flash story will become more intriguing as it makes its products available. Besides Project X, there is "Project Thunder," a PCIe-based shared storage appliance also due for release in 2013. EMC also ships solid-state drives (SSDs) alongside hard drives in its VMAX, VNX and Isilon storage arrays. "This is a step in the right direction," he said of VFCache 1.5. "When they start coordinating across storage and servers it becomes interesting, but they're not there yet."
EMC's Project X came from its May acquisition of startup XtremIO. EMC demonstrated the all-flash arrays for reporters at the conference, showing performance of more than 1,000,000 IOPS for random reads while running inline dedupe. EMC also revealed specs for the block-storage devices. They are 4U dual-processor boxes supporting either 8 Gbps Fibre Channel or 10 Gigabit Ethernet iSCSI, 10 terabytes (TB) of raw (7 TB usable) MLC flash capacity when loaded with 400 GB drives, and active-active cluster support that provides access to any volume through any port.
Josh Goldstein, EMC vice president of marketing and product management for flash, said EMC will support clusters of eight in the first Project X release. He said the nodes maintain latency at less than one millisecond with eight clusters.
Project X will also support instantaneous space-efficient snapshots and writeable clones. Goldstein showed the interface for quickly creating and mapping volumes, and said the system allows for quick virtual desktop rollouts for virtual desktop infrastructure (VDI) storage. He said Project X can reach more than 400,000 OLTP IOPS with a transactional latency of between 500 and 600 microseconds.