On Wed, 12 Nov 2008 12:42:31 -0500, Tony Harminc <[EMAIL PROTECTED]> wrote:
>OK, OK - you (and IBM) win! ... Tony, to the best of my knowledge, no one in IBM System z marketing, or for that matter, anyone with significant knowledge of the technical aspects of System z, has made official, public statements about specialty processors being features to boost performance. There may be a well-meaning sales rep or specialist or press person out there who does not have a full understanding of the hardware who have made that claim, but it should not have been an official IBM claim. As has already been stated, there is one notable exception to the "Specialty engines are not performance enhancers" rule - machines that run at subcapacity. If you have a box that doesn't run at the fully-rated uni speed, a specialty engine will provide better performance. There's one other "performance benefit," but it is a roundabout way of claiming that the specialty engine provides improved performance - if one were to install a zIIP or zAAP and relieve the general purpose CP pool of a CPU bottleneck, then that would indirectly result in a performance benefit by offloading Java and/or other MIPS and relieving the constraint on the GPs. Thus you got cheaper MIPS with the zAAP/zIIP and "fixed" a performance bottleneck. But that's obviously stretching things... FWIW. ---- Bill Seubert System z I/T Architect IBM Corp [EMAIL PROTECTED] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
