Yes, GRS using XCF is far superior in many ways, I would certainly not advise using GRS ring (without XCF) for a 4 way GRSplex, but using XCF it would certainly work. Of course, GRS-Star would be even better, but that is a little trickier. BTW, for small packets of data, I believe ESCON links are actually faster than FICON. I think I have seen a paper on this, but I can't remember where.
>>> Mark Zelden <mark.zel...@zurichna.com> 8/10/2009 9:41 AM >>> On Sun, 9 Aug 2009 21:01:42 -0700, Gibney, Dave <gib...@wsu.edu> wrote: > >True, and last time we revamped the IODF I had the required CTC(s) >added. That was over a year ago when we brought in the z9-BC and is the >last time I had a chance to take a baby step that direction. Also, on >this list, I'm led to understand that our four would LPARs push or >exceed GRS ring performance. > Yes, for the "old" GRS ring, 4 systems would probably be a bigger performance hit than you would ever want. However, if you set up a basic sysplex, GRS performance using XCF is better than dedicated CTC links. Especially since you can have FICON CTCs. Dedicated GRS links (what I referred to as "old" above) can't get any faster than ESCON in basic mode. So even XCF links using ESCON in CTC mode is faster and may give you acceptable performance with 4 systems. As usual, YMMV. I can't say I have been in any 4 system GRS ring (using XCF) shops in the last 10 years, so perhaps someone with that configuration can share. I do have plenty of experience with GRS ring prior to sysplex and I can say that even a 3 system ring presented some performance.. um... challenges. :-) Mark -- Mark Zelden Sr. Software and Systems Architect - z/OS Team Lead Zurich North America / Farmers Insurance Group - ZFUS G-ITO mailto:mark.zel...@zurichna.com 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 lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html CONFIDENTIALITY/EMAIL NOTICE: The material in this transmission contains confidential and privileged information intended only for the addressee. If you are not the intended recipient, please be advised that you have received this material in error and that any forwarding, copying, printing, distribution, use or disclosure of the material is strictly prohibited. If you have received this material in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the material. Emails are not secure and can be intercepted, amended, lost or destroyed, or contain viruses. You are deemed to have accepted these risks if you communicate with us by email. Thank you. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
