On Fri, 27 Oct 2017 08:36:02 -0700, Lizette Koehler <stars...@mindspring.com> wrote:
>Dear List - > >I have been reviewing some parms that have been around in z/OS for a few >years/decades? > >USEZOSV1R9RULES > >VSM USEZOSV1R9RULES(NO|YES): YES causes GETMAIN and STORAGE OBTAIN behavior to >be unchanged from its historic behavior. NO causes GETMAIN and STORAGE OBTAIN >behavior for user-region private area subpools that are both below and above >the >line to be implemented. Thus DQEs can be merged where possible. The default is >YES to provide a seamless migration. However, IBM recommends that you specify >USEZOSV1R9RULES(NO) to obtain a performance benefit for applications with long >DQE/FQE chains for user-region private area subpools. > >To Display: D DIAG > Wow, this is a very old item I forgot about. I never revisited USZOSV1R9RULES after z/OS 1.10 so it is defaulting to YES. I wonder what benefit it would be in some of my sysplexes with very large DB2 subsystems. I'm surprised there hasn't been a health check written for it by now since it came in a t z/OS 1.10, but I do recall hearing of some problems from people changing the option to NO, probably some of them on this LISTSERV. Maybe that's why the default hasn't change yet and there is no health check recommending the change. It may be one of those parms that you know you have a problem or when IBM support recommends changing it. Curious now to see what others say about it. If changing it to NO would save CPU cycles from DB2 on our large sysplexes, I'm all for it! Regards, Mark -- Mark Zelden - Zelden Consulting Services - z/OS, OS/390 and MVS ITIL v3 Foundation Certified mailto:m...@mzelden.com Mark's MVS Utilities: http://www.mzelden.com/mvsutil.html Systems Programming expert at http://search390.techtarget.com/ateExperts/ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
