That's fine, I don't agree. Thanks for checking for the documentation. I would have killed for a zAAP when we tried to go WAS V5 years ago. I would not have taken a GP either since the startup of the cell group dimmed the lights and having a GP, that was knee-capped, would have been a disadvantage over having a fully blown zAAP engine to support this workload. We had the estimation tool when it was a zap and the numbers came out in the log and showed the amount of java eligible work but I do not remember seeing switch rate information.
--- On Wed, 2/3/10, Mark Zelden <[email protected]> wrote: From: Mark Zelden <[email protected]> Subject: Re: IBM countersues Neon over zPrime accelerator To: [email protected] Date: Wednesday, February 3, 2010, 5:40 PM On Wed, 3 Feb 2010 08:34:21 -0800, Patrick Falcone <[email protected]> wrote: >Really? Is engine switching overhead with SP's and GP's CP's more of a concern versus running WAS with GP CP's and other traditional workloads from a performance perspective? > >Hmm. I've been there, no SP's, and it can be very ugly. I'm not sure I follow you...So are you saying zAAP's really don't help the overall performance of a mix of WAS and traditional workloads when running this type of mix on the same LPAR? > No - not compared to the same number of total GP engines. There is switching overhead to move the zAAP eligible workload. In the early zAAP days, there was quite a bit of tweaking to the JVM to determine when it made sense to switch or not. There were also some estimation tools to help you determine what part of your application could run on a zAAP (prior to the RMF changes that gave you the numbers) and the switch rate (I don't know if there are any switch rate numbers in SMF records, but I don't think there is). I was looking for some SHARE sessions that could explain all of this, but the ones I have looked at don't have the slides attached ("dispatcher changes to support zAAP", "everything zAAP" were a few I looked at). I stopped looking after that. Maybe someone else can point you to documentation or white papers or wants to provide more details. Mark -- Mark Zelden Sr. Software and Systems Architect - z/OS Team Lead Zurich North America / Farmers Insurance Group - ZFUS G-ITO mailto:[email protected] z/OS Systems Programming expert at http://expertanswercenter.techtarget.com/ Mark's MVS Utilities: http://home.flash.net/~mzelden/mvsutil.html ---------------------------------------------------------------------- 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
