IT Management

A number of indicators point to the continuing commitment to, and market for, the IBM mainframe platform.


Platforms “on the way down” drop investment in new functionality and technology. IBM appears to be shrinking investments in the very-low-end market (VSE, VM and systems smaller than 80 MIPS) to allow continued investment in z/OS and zSeries. As an example, besides the 64-bit addressing added with the z/Architecture, IBM has now committed to modifying z/OS to support more than 16-way symmetric multiprocessing by year-end 2004 (0.8 probability). IBM has also attacked other limitations, such as doubling the number of I/O channels to 512 and the number of logical partitions to 30 with plans to increase the number of logical partitions again to 60 by year-end 2004 (0.8 probability). Although total investment in the mainframe is shrinking to match shrinking mainframe revenue, IBM continues to consider the business as worthy of investment and has shifted to a smarter, more focused investment model.


In 2001, there were more than 70 new customers of IBM mainframe systems, and, by year-end 2002, there were another 100 or more new customers. That is compared to approximately 30 to 35 a year in the 1990s. Although by Unix, Windows or Linux standards that is not a large number, it is a good number for mainframe systems. At the same time, during 2002, the number of customers leaving the platform was probably more than 200.

The important factor is that the new systems ranged from 80-MIPS to more than 1,000-MIPS systems, whereas more than 80 percent of those moving off the mainframe were less than 40 MIPS, and many of them in the 3- to 15-MIPS range. IBM does not have a solution below 40 MIPS and will not have one in the future (0.9 probability), so it will continue to lose the very-low-end mainframe, which represents an extremely small amount of the total mainframe revenue. A small amount of the movement off IBM mainframes will continue to use the IBM mainframe operating systems on small systems that emulate the S/390 architecture.


The growth of Linux on the mainframe has been a surprise to almost everyone, including IBM. Begun with a small effort produced by the IBM Germany Laboratory in Boebligen, Germany, it grew to account for at least 15 percent of the net new MIPS shipped in 2001 and grew to more than 20 percent of the net new MIPS shipped in 2002. Much of the Linux MIPS capacity shipped in 2002 was as trials — it is important in 2003 that IBM get as many as possible of those trials to “stick.” More than 300 IBM mainframe customers have at least one Linux application in production on their IBM mainframes, and more than 400 additional enterprises are evaluating or in the process of implementing production Linux applications.

Greater than 80 percent of the Linux applications being implemented on the mainframe are infrastructure applications, such as Web, print/file and mail serving. The use of Linux in general, and especially Linux on the mainframe, for application areas such as database servers or heavy transaction servers has not yet become a significant factor. Also, a thorough total cost of ownership (TCO) analysis should be performed before committing to an active Linux-on-the-mainframe implementation plan.


3 Pages