EMC optimizes VNX hybrid array for flash
- 04 September, 2013 09:02
Brandon Robinson, director of network services at energy trading company Aces, an EMC shop, at the VMworld conference in San Francisco.
EMC's VNX hybrid storage line is now built for flash first, with revamped software that can take full advantage of multicore processors, producing what the company calls a major boost in performance.
As the cost of flash media falls and more enterprises turn to it for faster access to at least some of their data, hybrid arrays of both SSDs (solid-state disks) and HDDs (hard disk drives) are becoming an enterprise storage mainstay. Getting the full benefit of flash in those platforms requires more than just installing SSDs in place of spinning disks, so EMC and others are upping their game to increase speed across the board.
EMC is unveiling the new generation of its more than two-year-old VNX line at an event in Milan on Wednesday and presenting it as a major advance for the midrange storage platform. Whereas the current VNX is designed for HDDs and can accommodate SSDs, the new platform was built from the assumption that all customers would put in at least some flash, said Eric Herzog, senior vice president of product management and marketing. As before, the system can also be configured entirely with flash. "It's designed to make flash as fast as possible," Herzog said.
The software in the new generation of VNX is multithreaded and uses load balancing to spread its workload over all the cores in the system. That's a step up from the current software, which dedicates each core to one type of work. As a result, it can reach high utilization rates for all cores and not leave as much processing power unused. That's the key to its performance, he said.
"It's not just because they chips are getting faster, it's because all the cores are being used," Herzog said.
The performance gains from this and other improvements of the line are dramatic, according to EMC. With a similar configuration, a VNX from the current generation would top out at 240,000 IOPS (I/O operations per second) and the new version would reach 1.1 million IOPS, Herzog said. The VNX's bandwidth has tripled and its maximum capacity has doubled from 3PB to 6PB.
The result is that an enterprise can put more virtual machines on a VNX and its virtualized applications can run as much as four times faster, according to the company. EMC also says customers can get more bang for the buck. Because the new VNX uses processing power more efficiently, some enterprises will be able to buy a smaller VNX to do the same work, depending on the type of workload. EMC says this effect means a given customer could get the same performance for one-third the cost.
"We see some immediate performance improvements in bringing data into cache," said Brandon Robinson, director of network services at Aces, a power management company that uses the current VNX and has tested the new generation. Aces handles energy trading for mostly small energy companies and also crunches data to answer questions such as whether a utility should build a new power plant or buy the power from another producer. Its data is growing by about 30 percent per year, a rate that's likely to accelerate, Robinson said.
With more usable processing power, the new system can run EMC's FAST caching software with greater granularity, moving smaller chunks of data between HDDs and flash, Robinson said. As a result, more of what gets cached is actually highly active data as it should be, he said.
In the new platform, Aces also can use all the logical paths between its servers and storage at the same time, Robinson said. With the current generation, some paths need to remain on standby in case of a failure. The update means data moves faster and the system can recover more smoothly if some of the paths fail, he said.
"In the existing generation we get a little bit of performance and a lot of redundancy, and in the new system we get a lot of performance and a lot of redundancy," he said.
Hybrid arrays are in the sweet spot for many enterprises because they are more economical than all-flash systems, and optimizing them for flash is the direction of the industry, IDC analyst Ashish Nadkarni said. EMC's ability to squeeze more performance out of the same amount of processing power could help to lower IT managers' acquisition costs, he said. "Even if your budget stays flat, you can actually acquire the same capacity for either the same or lower cost," Nadkarni said.
The VNX still can't scale out as much as some newer platforms, such as EMC's upcoming Xtremio all-flash array, because it can only have two controllers. The Xtremio gets another controller with every module that's added to it.
"The VNX is, in a way, a legacy platform," Nadkarni said. "Within the context of a dual-controller system, I think it is a significant step forward."
EMC plans to keep both platforms going forward, with the less expensive VNX being an alternative to the faster Xtremio system, EMC's Herzog said.
Also on Tuesday, EMC will announce a variety of other offerings, including XtremSW Cache 2.0, a new version of its software for on-server cache with claimed lower latency and easier management. Later this month, the company will announce the inclusion of the new-generation VNX technology in the Vblock computing, storage and networking platforms that combine Cisco Systems, VMware and EMC components.
The new VNX line and XtremSW Cache 2.0 are available now. The street price of the new VNX series starts under US$20,000. The current VNX generation will remain available for three or four quarters, Herzog said.