isham research
IBM rejigs z/OS strategy ready for its next mainframe
IBM's next mainframe - due in May 2003 - will incorporate architectural changes as important in their way as the expansion of storage addressablity to 64 bits. For the first time more than 16 processors and 256 channels will be supported - both meaning major changes to the z/OS and possibly z/VM operating systems. Just as with MVS/XA, MVS/ESA and z/OS itself, it's important that as many users as possible migrate to a 'positioning' release - in this case z/OS 1.4. The problem is that many users have been holding back - particularly to the older OS/390 2.10 release because it permitted 31-bit addressing fallback.
Today's announcement contains a package of measures designed to promote this migration. Chief among them is the Bimodal Migration Accomodation Offering - a no-charge feature permitting z/OS 1.2 to 1.4 to execute in 31-bit mode on zSeries hardware. Many customers have been wary - rightly, as it turns out - of changing software, hardware and architecture in a single step. For them, OS/390 2.10 became their 'port in the storm' and a significant number have no immediate plans to move off it. Workload Level Charges are also perceived by some - sometimes rightly - to be higher than Parallel Sysplex License Charges and require more complex administration.
The fact that z/OS 1.4 will be 'current' for longer than any release of MVS in recent history is also an incentive to migrate to it. z/OS 1.5 will not now ship until 1Q04 - up to eighteen months after z/OS 1.4 becomes available. During this period - and perhaps afterwards - IBM will ship new MVS function via the 'Small Programming Enhancement' mechanism. Both the reduced frequency of z/OS releases (annual in the future, instead of bi-annual) and the return to SPEs are broadly welcomed by users - but they represent a significant reversal of IBM's previous position:
The integration [of many components into OS/390] eliminates separate orders, eliminates separate prerequisite or corequisite checks, eliminates separate installations and customer testing after each step.
IBM Announcement Letter 296-018, 20 February 1996
The use of SPEs will allow users to exploit the functionality of new hardware such as the next mainframe itself and future peripheral products such as DASD subsystem without having to migrate their entire environment to a new release of the operating system. DFSMS, in fact, is likely to be the first beneficiary.
Activity on the IBM License Manager front remains minimal.
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