isham research
(This discussion has been overtaken by events. The current version will be found here)
One of the major issues IBM faces in the medium and long term with its zSeries (Freeway) mainframe systems is the complete and utter lack of affordable development platforms for small ISVs. A proposed low-end 64-bit system - codenamed 'Flagstaff' - was cancelled in September 1999 and many have been waiting for a replacement to be announced. The [Numaq] is not it. And nor is this. The European version was a bit more precise on performance, but the press release a day or two later confused the issue for a few days by omitting OS/390 entirely.
The 'Flagstaff' replacement - apparently officially known as M390 but usually referred to as 'Subway' - will probably be built for IBM by Hitachi and will use a five-way MCM to deliver one to three G7 processors for customer use. One processor is reserved as a SAP and one as a spare. Since this system is also intended for the Japanese VOS domestic market, IBM (who will supply the processor chip) will have to restore the VOS functionality they deleted in the move from G6 to G7 - a good opportunity to fix a few other bugs in the design, which has already seen a number of disruptive microcode upgrades. Not good for a 'continuous computing platform'.
Subway, however, would start somewhere between 150 and 180 MIPS. The G7 processor - even before the extensive rework it will have - is just too powerful for small and medium System/390 mainframe users. MCM packaging is also too expensive for single-chip systems. As Dan Colby - head of IBM's System/390 efforts - said to an auditorium full of IBM Business Partners at Partnerworld 2001 in Atlanta - "Below 60 MIPS the only solution is emulation."
By the middle of 2002, this 60 MIPS will be 150 MIPS. At present, the only commercial System/390 emulation game in town is Fundamental Software and its partners with their FLEX-ES software - the same software as IBM's x/EFS. In Europe, T3 Technologies is opening a base in Munich and NMC is building a demonstration and competence centre in Hamburg. There are other IBM mainframe emulation efforts, notably Hercules and UMX Technologies - the former is an open source effort principally involving amateur retrocomputing and the latter has no discernable installed base. One major differentiator is hardware. Fundamental Software is somewhat mis-named; their products also include PCI channel cards and a communications adapter card. Although emulation runs much better using internal disks and emulated tapes, many small and medium users need to attach peripheral devices - especially printers.
IBM's NUMA-Q product seems to be taking hit after hit. Already premium-priced because of its potential scalability and still only 'generally available' with 700MHz processors, IBM has now reversed its earlier intention to support Windows Data Center Server on the xSeries x430 platform. IBM's 1GHz xSeries (Netfinity) range, in particular, now employs a lot of ex-mainframe technology and OS/390 itself is still one of the world's most stable and secure operating systems.
It's obvious now that other emulations must come. With IBM having declared support for Linux on all platforms, a 64-bit Linux port of FLEX-ES would provide System/390 compatibility on all IBM's servers. There is a distinct need for z/Architecture development systems, and also both 31-bit and 64-bit IBM mainframe architectures running on medium-sized systems under 64-bit Linux.