IBM equips Intel servers for mainframe computing

IBM's xSeries servers have grown from a belief that users should not be forced to acquire new Unix or mainframe expertise because...

IBM's xSeries servers have grown from a belief that users should not be forced to acquire new Unix or mainframe expertise because their Intel-based systems run out of steam as data volumes grow, writes Nicholas Enticknap

IBM is better known for its zSeries, iSeries, and pSeries ranges than for its Wintel servers. But the company has been quietly building a strong position with the less-well-known Intel-based xSeries range, especially in the US, where its market share rose by 2.7% in the second quarter of 2002.

IBM has been pursuing a policy of making its Intel-based products more attractive by adding top-end server features from its other ranges since the launch of the Netfinity range in 1997. The idea was to differentiate its products from those of its competitors while retaining the low-cost emphasis. Netfinity products were built according to a blueprint known as X-architecture (with "X" pronounced "cross" as it involved bringing across technologies from other ranges).

Examples of such features are Chipkill memory (advanced error-correcting memory brought across from the RS/6000) and light path diagnostics (a technology for rapid diagnosis and correction of problems that was initially developed for mainframes). "X-architecture comprises capabilities not previously present in the Intel market, so this is our product differentiation," says IBM's xSeries communications manager Vince Smith.

In October 2000 the Netfinity range was renamed xSeries. One year later IBM announced Enterprise X-architecture, described by Smith as "a logical extension of X-architecture to enable Intel servers to do mainframe computing". The theory is that many user companies now only have Intel-based skills among their IT professionals, and they should not have to acquire new Unix or mainframe expertise because their Intel-based systems run out of steam as data volumes grow.

Enterprise X-architecture consists of two major elements. At the core is a chipset, codenamed Summit, which works with Intel processors to provide mainframe levels of reliability and availability. "How do you build a robust system that uses industry-standards, DRams and chips? That is the challenge," explains IBM's chief hardware engineer Guru Rao.

Summit has four components: a large Level 4 cache for improving performance; new memory technology for greater reliability; an interconnect to allow the linking of multiple Intel processors without degrading performance; and a feature called remote I/O, which is designed to offset some of the limitations of using a traditional Intel I/O bus. The chipset is the first for the Xeon MP from any manufacturer.

The hardware features of X-architecture are supported by a system management software product called IBM Director, which is shipped as standard with every xSeries server.

IBM Director was originally a subset of IBM subsidiary Tivoli's IT Director, but has been enhanced with a number of new features. These include capacity planning capabilities from the iSeries which warn users of impending bottlenecks and advise on appropriate corrective action; and software rejuvenation, which predicts when software failures are likely to occur, corrects them when possible, and makes recommendations for planned rebooting when not.

Key differentiator
Tony Lock, senior analyst at Bloor Research, believes IBM Director is the key xSeries differentiator. "The x440 is unique on the hardware side, but hardware uniques always disappear. The big difference is the management philosophy they have wrapped around the hardware," he says.

All of these hardware and software features are incorporated in the current flagship of the xSeries range, the x440, which was launched in March. This is an evolution of the old Sequent Numa (non-uniform memory addressing) architecture.

The x440 uses Intel Xeon MP processors, with two or four chips being housed in a 4U (7in)-high box. IBM offers both an eight-way and a 16-way version. The x440 features both physical and logical partitioning.

Blue-chip users such as Morgan Stanley believe IBM's new recipe works. "We have been very interested in leveraging the commodity of Intel-based servers to support some of our application and infrastructure workload," says Richard Anfang, Morgan Stanley's managing director. "We are hoping to utilise the power, reliability and scalability of the IBM eServer x440 system that are the minimum requirements for these distributed applications."

Lock believes the only effective competitor for the x440 is the Unisys E7000. This product was the first "Intel mainframe" - a product with more than eight processors for running Windows 2000 Datacenter. However, it has achieved only modest sales to date.

This suggests the market is sceptical about the ability of an Intel system to do the job of a mainframe without being equipped with features that bring the price up to the same level. IBM is aware of this, and stresses its competitive pricing, with a 16-way x440 priced at just over $100,000 (£70,000) - 78% under the Unisys list price. An entry-level two-way x440 (without discs) costs just £14,375.

Judging performance
IBM claims the metric to judge the x440 by is not conventional price/performance but "return on availability". Here the company says it is 20% to 30% better than Dell, its nearest competitor, according to Gartner figures.

The x440 is the leading-edge product in a large range. The xSeries comprises two separate product lines, universal servers and rack-optimised servers, both of which feature between one and eight processors. The entry-level x200 server has a starting price of just £549. All run Windows and Linux. The xSeries also contains a number of special-purpose appliances, mainly for improving Web performance but also including network-attached storage systems.

Using these products, IBM's intention is to double its market share over the next few years, taking advantage of both its own unique technology and the pressure Compaq faces following its takeover by Hewlett-Packard.

Phil Dawson, an analyst at Meta Group, believes Microsoft's delay in producing the .net release of Windows will hurt IBM by giving Compaq and HP time to regroup, pointing out that both companies "are extremely close to Microsoft". But he adds that IBM is in a strong position, with the x440 having "a year's advantage in a technology sense over Compaq, and two years over Dell".

xSeries technical details
High-density packaging is a big selling point of the xSeries. The flagship 16-way x440 fits into a unit just 8U high (eight rack units of 1.75in, giving a total of 14in), compared to the 40U of the only other 16-way Intel machine available today, the Unisys ES7000. An eight-way x440 fits into a 4U package, while the dual-processor x330 occupies just 1U. IBM intends to extend this principle by adding blade servers that occupy less than 1U of space to the xSeries shortly. IBM claims one customer, Shell Exploration, has a Linux cluster of 1,280 xSeries servers, packed 42 to a rack.

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