By Timothy Prickett Morgan
Hoping to stimulate interest in the its S/390 G5 servers and attract attention away from the looming announcement from Hitachi Data Systems of its Skyline II mainframes, IBM yesterday divulged a complex set of tweaks to the microcode at the heart of the G5 servers that make them easier to upgrade and offer advanced features like hot pluggable I/O that are becoming common on both PC and Unix servers. While these announcements are important to those that use IBM mainframes, they are more indicative of a huge opportunity for mainframe customers to make both IBM and Hitachi Data Systems, and Amdahl if it tries at all to sell mainframes in 1999, really sweat it out. It’s only the fourth week of the year, and IBM has already fired the first volley in a massive PR campaign for the hearts, minds and dollars of the mainframe market, trying to peddle products that probably won’t be available until the fall. Hitachi Data Systems is expected to actually announce the Skyline IIs during the first quarter, even though it doesn’t expect to be able to deliver them until September. But Hitachi Data Systems and its parent company, Hitachi Ltd, have little to lose by talking about and then booking orders for their new servers nine months early. IBM has plenty to lose, which is why it seems to be pulling S/390 G6 server technology ahead and delivering it in the G5 line. Specifically, the G5s now include a new set of microcode that allows customers to add processing power to their machines without having to take them offline. Despite what it says in the press release – customers can upgrade their systems when they need to, all the way from a uniprocessor to a 10-way server, without disrupting their business, according to Brenda Zawatski, director of enterprise systems at IBM’s S/390 division – the new Capacity Upgrade on Demand upgrade function that comes with the new microcode has very specific limitations. To understand them, you have to know how S/390s are built. An S/390 multi-chip module (MCM) has six full S/390 CMOS chips, running at between 420 MHz and 500 MHz in the case of the G5s. S/390 servers can have one or two of these MCMs, and depending on how many IBM turns on, they can have from 1 to 10 active processors in those servers (two of the chips are used as either hot spares or I/O controllers). Capacity Upgrade on Demand, which allows for performance upgrades without having to take the machine down, only works on a machine that already has one or two MCMs installed and is using the same speed G5 engines. To move from a five-way server to a ten-way server, for instance, requires the same old upgrade and a weekend of hell. But moving from a two-way to a three-way or from an eight-way to a ten-way just requires activation of the microcode. Of course, to get the new microcode working under the S/390, customers with existing G5 servers have to take them down; the microcode will, however, be shipped on new G5s from the start. Capacity Upgrade on Demand is part of a larger IBM scheme called Plan-Ahead which seeks to get customers involved in capacity planning using IBM hardware during 1999 before they start thinking about HDS gear and to help them make sure they have the capacity on hand to meet Y2K challenges. Both are real threats to IBM. Part of the Plan-Ahead process is a G5 server feature called Concurrent Conditioning (again, a mix of microcode changes and performance tools), which allows customers to add or remove parallel channel, OSA-2, ESCON or the new FICON channel cards without taking their G5 servers down as they currently have to do. IBM has also announced a Capacity Backup Upgrade that allows IBM to quickly add processing power to a customer’s complex through remote data links in the event they run out of processing power. Concurrent Conditioning will be available on G5s starting February 26. Capacity Upgrade on Demand and Capacity Backup Upgrade are expected sometime in the second quarter, just about when IBM should start talking about G6 machines, unless something has gone wrong with its G6 development plan. IBM raised more than a few eyebrows when it said that it will backcast the functional enhancements it makes in the G6 series of S/390 processors into the G5 line. The exact nature of those G6 enhancements remains unknown, but it is very likely that today’s G5 tweaks were actually due in the G6 generation and that IBM has, for marketing reasons, decided to tell customers about them early rather than wait for Hitachi Data Systems to garner attention for its Skyline IIs. IBM wants to keep the G5s and the G6s in the front of its mainframe customers’ minds, because many of them will be sorely tempted by the prospect of a Skyline II processor with 260 or 270 MIPS of power in an engine that can be put into a 12-way server with about 2500 MIPS of aggregate processing power.
