George Henke observes: >The feedback I have gotten so far, based on a few private replies, is about >8 - 12 people per CEC.
Maybe, but that doesn't mean when you double the number of CECs you would double the number of people, or vice versa. That is, you can't extrapolate linearly in either direction, as our meat computers subconsciously often do. For example, let's suppose you were a "big" shop in the year 2002 and you were running 10 z900 machines, each configured as 213 models with a PCI of 2888 each. So you had 28880 PCIs total, plus some coupling facility engines. Then assume you experienced 8% per year compound growth in capacity (with transaction volume growth, etc. -- holding the application set constant for this example) so that after a decade you'd end up with approximately 62350 PCIs (28880*1.08^10). Well, that capacity would fit on a mere two CECs today: a pair of z196s, perhaps at capacity setting 742 each (31675 PCIs each). An ~80% reduction in floor space, which unfortunately probably got more than filled with more expensive and less reliable infrastructure. And actually, in practice, when you take 10 footprints down to 2 you tend to pick up some nice virtualization benefits, so that's probably too many PCIs, never mind possible zIIP and other benefits. So in that decade would you have also taken a staff of 100 people (10 per CEC) and reduced it to 20 people? That would be an order of magnitude jump in staff productivity per PCI over 10 years. That seems extreme. Perhaps you wouldn't have 100 people (if you started with 100), but I don't think you'd have as few as 20 either, ceteris paribus. I don't think there's any serious disagreement that the mainframe has led the way in providing huge productivity improvements just about any way you measure it. As a generalization, you mainframers are extraordinarily productive, both in comparison to your predecessors and in comparison to your non-mainframe peers. (Keep up the good work -- and more, please.) There are some analysts who have looked at this stuff and who concur with the sort of trends and characteristics I describe above. Mainframes are characterized by very strong scale economies. There are at least two ways to take advantage of that: be big(ger) -- more transactions, more volume, more batch with the same or similar application set -- and be broader -- more applications sharing the same mainframe infrastructure. That doesn't mean you can't do fine financially and otherwise running a single application at low volumes, but you can do even better bigger and/or broader. -------------------------------------------------------------------------------------------------------- Timothy Sipples Resident Enterprise Architect (Based in Singapore) E-Mail: timothy.sipp...@us.ibm.com ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
