On Wed, 11 Apr 2012 10:24:10 -0400, Mark Jacobs <mark.jac...@custserv.com> wrote:
>We had a discussion yesterday regarding our obsolete IEFUSI exit and how >it should be modernized to even know about the virtual storage region >above the 2GB line. > >One of the concerns was that since IEFUSI has no practicable effect on >authorized programs I was asked to come up with some ways to better >manage our environment just in case some user decides to allocate and >start using massive amounts of above the bar storage. > >My question to the mailing list is do you manage towards this scenario >and if so, how? > I'm not really worried about STCs and authorized users. Nothing I can do about them except allocate 2000 page volumes (just kidding). The comments in my IEFUSI exit from 2005 still hold true and explain what I am doing. So far, it has worked out fine. My client does have 64-bit usage and also large pages running 64-bit WebSphere. Basically, I just want to keep someone from "playing" with 64-bit from destroying the system. My SMFPRMxx MEMLIMIT is to 10G. 9/14/2005 M ZELDEN FORCE MEMLIMIT OF 5G FOR ANY JCL SPECIFICATION OF ANYTHING OVER 5G BUT ALLOW MEMLIMIT NOLIMIT (16383PB) IF REGION=0M. IF NO JCL SPECIFICATION IS USED (OTHER THAN REGION=0M), THEN TAKE THE MEMLIMIT DFLT FROM SMF (SMFPRMXX). THIS WILL ALLOW SYSTEMS THAT NEED A HIGHER MEMLIMIT TO HAVE SMFPRMXX BE THE CONTROLLING FACTOR - AS LONG AS MEMLIMIT IS NOT SPECIFIED IN THE JCL. SINCE ONLY STCS CAN USE REGION=0M, ONLY STCS WITH REGION=0M CAN GET MORE THAN THE FORCED MEMLIMIT OR THE SMF DFLT. By having SMFPRMxx be the controlling factor, I could easily raise it if a problem came up with no JCL changes etc. So far, I've haven't needed to do that. Keep in mind I updated this exit for the brave new world in 2005. I'm slightly surprised it's been 7 years and I haven't needed to modify it except for a change in 2007 related to OA14391 which affected z/OS 1.7 & z/OS 1.8 and above. That APAR kept STCs with REGION=0M from getting MEMLIMIT=NOLIMIT so I updated the exit to force MEMLIMIT=NOLIMIT for STCs with REGION=0M (which was the behavior prior to OA14391). Regards, Mark -- Mark Zelden - Zelden Consulting Services - z/OS, OS/390 and MVS mailto:m...@mzelden.com Mark's MVS Utilities: http://www.mzelden.com/mvsutil.html Systems Programming expert at http://expertanswercenter.techtarget.com/ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN