The Four Hundred

EMC, the storage hardware vendor that has been dogged by declining sales since the dot-com blowout, pulled a rabbit out of its hat two weeks ago and announced a radical redesign of its high-end Symmetrix disk array based on its new high-speed Direct Matrix (DMX) architecture. Neither the mainframe nor the iSeries can connect to the new DMX arrays today, but EMC confirms that it's working on OS/400 support, which, sources say, could come as early as the third quarter of this year.

EMC says that the Direct Matrix architecture marks a significant departure from the bus- and switch-based architectures used in EMC's older and lower-end disk arrays, as well as the arrays from IBM and Hitachi Data Systems, EMC's primary competitors in enterprise storage. Instead of piping all reads and writes through a bus or a switch, the Symmetrix DMX series features dozens of dedicated paths that provide direct connections between the memory cache and the disk. EMC says its new, patented design leapfrogs the competition by completely eliminating bus arbitration and switching contention while delivering minimal data latency.

As a result, the new DMX arrays are simply fast. With up to 128 dedicated paths, each of which delivers up to 500 MB/sec in bandwidth, the DMX array's maximum total system bandwidth is a whopping 64 GB/sec, six times better than its nearest switch-based competitor, EMC says. By comparison, EMC's previous high-end disk array, the bus-based Symmetrix 8000 series, delivers a maximum total system bandwidth of 1.8 GB/sec. In terms of actual performance in live transactional environments, EMC says DMX delivers a two-fold improvement over the nearest competitors, and bests its competitors' performance in decision support environments by a factor of three. Perhaps more important, EMC's architecture is designed to scale as CPU, network, and disk drive technology improve over time, as they will inevitably do.

You could almost visualize Albert Einstein pondering the magnitude of the equation that made him famous from reading EMC president and chief executive Joe Tucci's comments on what went into the new DMX design. "We could follow the path of least resistance and develop an incrementally better bus- or switch-based Symmetrix, or we could take the more challenging road to much greater returns for customers. After consulting with our customers, the choice was obvious," he says. "The resulting Direct Matrix introduces a revolutionary new architecture, one with immediate order-of-magnitude leaps in performance and availability."

EMC has delivered three Symmetrix arrays based on the DMX architecture, all of which use 73 GB or 146 GB Fibre Channel drives (Seagate Technology is EMC's primary source) on 2 GB/sec Fibre Channel loops. The entry-level Symmetrix DMX800 offers only Fibre Channel connectivity, while the higher end DMX1000 and DMX2000 offer Fibre Channel and ESCON (mainframe) connectivity as well. The DMX series are powered by 500 MHz PowerPC processors, between 16 and 48 with FC connectivity, and up to 116 of them with a full complement of ESCON connectivity.

The entry-level Symmetrix DMX800 is a rack-mounted system that uses the same frame and disks and looks very similar on the outside to EMC's midrange Clariion disk array, but is very different inside. The DMX800 can be configured with 16 to 120 drives for a total capacity of up to 17.5 TB. It includes 16 FC drive ports, 16 FC I/O ports, and has between 4 GB and 32 GB of cache. The Symmetrix DMX1000 features 48 to 144 FC drives, for a maximum disk capacity of 21 TB, and between 4 GB and 64 GB of cache. The DMX1000 can support from 16 to 48 2 GB/sec FC drive ports, and up to 48 ESCON channels. The DMX2000 basically consists of two DMX1000s bays attached side-by-side. It features between 86 and 288 disk drives for a maximum raw capacity of 42 TB, between 8 GB and 128 GB of cache, 16 to 96 FC ports, and up to 96 ESCON channels. EMC is also offering high-performance variants of the DMX1000 and DMX2000, called the DMX1000-P and DMX2000-P, which have optimized ratios of disks to back-end channels for read-write intensive applications that require the maximum speed, such as data warehousing.

While the new DMX series arrays are pricey--the new DMX800 ranges in price from $409,000 to $931,000, while the top-end DMX20000 tops out at $2.5 million--EMC maintains that they are competitive from a price-performance standpoint. For example, a Symmetrix DMX800 system configured with 7.2 usable TB offers up to three times higher performance, at a list price that is 30 percent lower, than last year's Symmetrix 8530 system with the same capacity, EMC says. Similarly, EMC says users will pay 44 percent less for a new DMX1000 configured with 18.5 TB than a similarly configured Symmetrix 8830, and it will be three times faster to boot.

EMC has updated its Symmetrix operating environment, Enginuity, to handle the increased capabilities of the DMX series, while maintaining backward compatibility with existing Symmetrix arrays, which will allow companies to use their old Symmetrix arrays as remote site mirrors. The company is also offering updated versions of its high availability mirroring software, Symmetrix Remote Data Facility, its flash-copy utility, EMC TimeFinder, and its backup and recovery software, EMC DataManager. Unix, Linux, Windows 2000, and Windows NT operating systems are supported by the new DMX series and Enginuity operating environment, and EMC has committed to supporting mainframes, via FICON support, in the third quarter of 2003.

In terms of OS/400 support, an EMC spokesman said that the company is committed to supporting OS/400 and the iSeries with its new Symmetrix DMX series, but could not provide a timeframe for such support. EMC is the only provider of external disk arrays to AS/400 and iSeries servers besides IBM, and EMC estimates it has about a 20 percent share of the iSeries and AS/400 disk array marketplace.

While EMC's tight-lipped policy regarding future directions did not permit the EMC spokesman to provide a timeframe for supporting the iSeries with the DMX arrays, a source who is an OS/400 user of Symmetrix arrays says his EMC contact told him that iSeries support is scheduled for this fall.