EMC's long-awaited entry into all-flash storage arrays will finally get a full-fledged rollout next week, possibly setting the terms for mastery of the fledgling product category along the way.
The array, acquired through EMC's purchase of startup XtremIO about 18 months ago, is designed so that enterprises can steadily build up their capacity and performance to keep up with growing demand. Each so-called X-Brick in an XtremIO cluster comes with two controllers to ensure high availability. Adding a new X-Brick brings in two more controllers along with the additional capacity, and the power of all the controllers gets pooled across the cluster.
XtremIO's long journey from acquisition to general availability created some suspense as EMC, the most dominant storage player, prepared its first array designed exclusively for flash. Many enterprises are adopting solid-state storage in various forms, but all-flash arrays can realize more of the technology's performance edge than do systems that combine spinning disks and flash.
EMC's entry comes in the form of an x86-based device one rack unit high with 10TB of storage capacity. Another 1U model with 20TB is coming next year. Each box has 256GB of memory, which can be pooled across a cluster of as many as eight X-Bricks for a total of 2TB of memory, said Josh Goldstein, vice president of marketing and product management for XtremIO. The system includes in-line data deduplication for efficiency, and data is distributed across the cluster for load balancing. Infiniband links the X-Bricks, using RDMA (remote direct memory access) to distribute incoming blocks of data among controllers and reassemble the data to be read.
Other all-flash arrays allow enterprises to add storage capacity but have a set number of controllers, so the strain on those controllers grows as more storage is hooked up, Goldstein said.
The XtremIO architecture should make storage performance predictable as enterprises scale out their arrays, which can make life easier for IT departments, Enterprise Strategy Group analyst Mark Peters said. It's even more important than the top I/O speed that a system can hit, he added.
"Any user can deal with just about anything from their equipment as long as it's predictable," Peters said.
Not knowing how fast an application or VM will get the data that it needs can make it harder for enterprises or service providers to meet service level agreements, and it can force them to buy more capacity than they really need just to make sure they're covered, Peters said.
By focusing on predictability, EMC is giving customers something useful but also shaping the conversation about all-flash arrays through sheer market share, Peters said. EMC could have emphasized another characteristic, such as maximum I/O performance or integration with management tools, but didn't.
"EMC is defining the playing field in an area that really suits them," Peters said.
Startups and other mainstream storage vendors, including NetApp and IBM (through its Texas Memory Systems buyout) are also moving into all-flash arrays. But EMC's entry puts critical mass behind the market, Peters said. "The story of the joy of flash is going to be told more aggressively ... than it was before," Peters said.
XtremIO will allow CMA Consulting Services to more easily build Oracle rack clusters with storage for its clients in health care and human services, said Brian Dougherty, CMA's chief architect. The Oracle clusters include Linux servers, InfiniBand interconnects and storage.
"Traditionally, the storage nodes, for us, have been more of the monolithic, larger storage arrays that we would configure and pre-deliver. But now the storage node for us will be the XtremIO X-Brick," Dougherty said. The X-Brick can deliver the same capacity and performance in far less space and be scaled out in the same linear way as the computing element, making for easier expansion, he said. Using all flash is more expensive, but the savings in build time, rack space and power more than make up for that, he said.
What Dougherty still wants to see is more density, coming in the 20TB array next year, and software for continuously replicating to a peer XtremIO cluster at a disaster-recovery site.
The XtremIO system will be generally available beginning next Tuesday. It took this long to reach the general market because EMC bought the technology in progress and had to finish it, Goldstein said. Shipping an EMC product also takes more preparation than putting out gear from a startup, he said, speaking from the experience of having worked at several startups, including XtremIO. Manufacturing capacity, quality assurance and channel training are all parts of the process, he said.
Emerging from under the temporary moniker Project X in March, the XtremIO system was released in April under "directed availability," in which EMC qualified the customers that wanted to buy it. Hundreds of these IT shops have deployed XtremIO arrays in production environments, Goldstein said.
Enterprises have already been able to deploy some EMC arrays, including the latest version of its VNX platform, entirely with flash storage. But the VNX is designed as a hybrid system. XtremIO is the high end of EMC's arrays in terms of performance, intended for enterprises with highly demanding applications such as virtual desktops and online transaction processing. EMC would not disclose pricing.