IT Management

For the past several years, open systems storage has dominated the storage industry, with companies focusing on networking their server-attached storage and consolidating storage into SANs. To this end, midrange storage has grabbed the spotlight, as vendors have rushed to introduce midrange products, such as IBM’s FastT and EMC’s CLARiiON systems, which introduce mainframe-like features and storage capacities at a significantly reduced cost. Some industry analysts even observed that other than cost, the distinctions between mainframe and midrange storage were blurring.

Outside of the spotlight, however, mainframe storage vendors continue to bolster their high-end offerings. The big three mainframe storage vendors—IBM, EMC, and Hitachi Data Systems—have been quietly boosting the high end of their product lines to address the storage needs of organizations with the largest mainframes. The vendors seemingly are playing an ongoing game of one-upmanship, each announcement leapfrogging the latest announcement of its rivals. As a result, the amount of terabytes sold continues to increase even as industry revenues decline or remain flat due to lower prices.

For mainframe storage managers, this means a steady stream of innovative features and performance gains while prices remain in check. The prolonged economic downturn, which is only just starting to show signs of improvement in the technology area, along with the historic annual price/ performance improvements in storage, has further fueled what many IT managers say remains a buyer’s market, at least for now, as vendors try to drive their latest top-of-the-line storage products into the market. In addition, steady increases in the price/performance of storage will continue to drive down the price per raw megabyte of storage. Over the last 12 months, IBM, for example, adopted the Storage Networking Industry Association’s (SNIA) Storage Management Initiative - Specification (SMI-S), formerly known as Bluefin and CIM, its multivendor storage management specification for Enterprise Storage Server. In addition, IBM has bolstered the enterprise storage management capabilities of its Tivoli management offering for the zSeries. IBM also added high-speed (2Gbit) FICON capability for increased throughput, FlashCopy support for copying data, and Peer-to-Peer Remote Copy capability for disaster recovery. In terms of performance, IBM added 15,000 RPM, 72.8GB disk drives, which will boost disk drive performance up to 50 percent. It also is building its autonomic computing capabilities, such as auto configuration, capacity upgrade on demand, and SMI-Senabled monitoring, into all its ESS products through its Tivoli management framework. The ESS 800, the current top of the line, offers 55.9TB of storage capacity and fast connectivity, as well as faster processes and enhanced cache size.

Not to be outdone, EMC expanded the storage capacity and overall scalability of its high-end Symmetrix product line. The new top of the line is the Symmetrix DMX series built around a patented architecture, Direct Matrix. The new storage system will handle bigger workloads with better performance and be able to consolidate more storage in a single system. The top-of-the-line model DMX 3000, a triple-bay integrated system, provides up to 576 drives for a maximum capacity of more than 84TB. Additionally, it offers up to 128GB of global memory and 64 fibre channel host ports or ESCON channels. It also sports 32 FICON or Gigabit Ethernet (iSCSI) connections. The new EMC design generally avoids the traditional switch- and bus-based architectures commonly used in high-end storage. With DMX, EMC offers greater throughput with a point-to-point matrix interconnect consisting of up to 128 point-to-point connections running at 500MB per second for a total data path bandwidth of 64GB per second and total aggregate data path and messaging bandwidth of 72GB per second. This new architecture resolves performance issues around contention, latency and bandwidth constraints and enables the system to scale in linear fashion.

Hitachi followed suit. It enhanced the capacity, connectivity, and throughput options for the Hitachi Freedom Storage Lightning 9900 V Series highend RAID systems. For example, it supports the new 146GB drives, which effectively doubles the total raw capacity of the original Lightning 9900 V Series to 148TB (total usable capacity of 128TB) in a RAID-5 configuration, according to published specifications. It boosted connectivity with up to 32 FICON channels, 48 ESCON channels, and 64 fibre channel connections at 2Gbit per second. Like EMC, Hitachi also re-architected its high-end storage, adding its Hi-Star crossbar switch-based architecture, which it had introduced a year earlier.

“With DMX, EMC really reinvigorated its mainframe strategy,” says Peter Gerr, analyst, Enterprise Storage Group, Milford, MA. EMC was responding to the architectural changes Hitachi had incorporated in its Lightning line. “Hitachi’s switched backplane architecture really woke up EMC,” he continues.

At EMC, performance became a priority. “We have the fastest FICON implementation and provide high density,” says Chuck Hollis, EMC senior vice president. The company is also touting its replication capabilities.

Hitachi has focused on scalability and reliability. “We had the switch architecture before EMC. That gives us great scalability,” says Jim Beckman, Hitachi’s director of product marketing. Today, Hitachi claims to deliver the most capacity for a single system, 148TB.

Where EMC and Hitachi have been focusing on density, capacity, and performance, IBM is taking a different tack. It has been packing advanced features and management capabilities into the storage system. “Raw performance and amount of disk capacity is not the issue,” insists Jim Tuckwell, IBM’s ESS marketing manager. Instead, IBM touts its replication, long-distance disaster recovery, and flexible mirroring.

Of all the differentiators promoted by the vendors, capacity is the easiest to understand but is difficult to defend, according to Gerr. As soon as someone introduces a higher capacity disk drive, the capacity picture can change. And manufacturers are continually bringing out bigger drives. “In the end, capacity itself isn’t a differentiator. It’s just another check box on an RFP,” Gerr adds.

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