Jumping from 4 to 25 Gb isn't a good idea, but if I have 4 Gb used and 4 unused I think there's no difference in adding, say, 2 Gb (so using 6 Gb as total). Consider we have bursts or spikes in paging and for instance our DB2 isn't performing well even if 'all runs well' as someone say.
Anyway is there any rule of thumb, having z/OS 1.7, for max central storage ? I mean, is there a suggested value to avoid RSM overhead before z/OS 1.8 (1 Gb ? 5, 10 or which value for central storage) ? Thank you in advance Max Scarpa Mark Zelden <[EMAIL PROTECTED]> Sent by: IBM Mainframe Discussion List <IBM-MAIN@BAMA.UA.EDU> 07/11/2007 17.30 Please respond to IBM Mainframe Discussion List <IBM-MAIN@BAMA.UA.EDU> To IBM-MAIN@BAMA.UA.EDU cc Subject Re: Real storage usage - a quick question On Wed, 7 Nov 2007 10:22:30 -0500, Veilleux, Jon L <[EMAIL PROTECTED]> wrote: >In 1.7 RSM took more CPU when we increased our real storage since it had >to look at every frame for the UIC. It's a simple equation, more frames >more CPU to scan them for their UIC. Our performance area noticed that >there was an increase. I believe that it showed up as uncaptured CPU or >MVS usage under OMEGAMON CPU utilization. > Exactly. So if you are running below z/OS 1.8 and aren't paging, don't just add 25G of storage because you have it laying around doing nothing since you upgraded your processor and added all the "cheap" memory. We've discussed this before. 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 ---------------------------------------------------------------------- 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
