Have you upgraded your memory? If you have a lot of memory and are still on an older release of z/OS that uses the least recently used algorithm for memory management then RSM/ASM can grab a bunch of CPU. The newer releases handle memory management in a more CPU friendly manner.
Jon L. Veilleux [EMAIL PROTECTED] (860) 636-2683 -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Chris Burgess Sent: Thursday, October 11, 2007 7:41 AM To: [email protected] Subject: Re: Logical to Physical CPU ratio ROT (was Re: IXC454I messages) I'll check it out. We have observed what appeared to be high CPU utilization on LPARs with no workload running on our z/9's. We haven't quite got a finger on it yet but we have also noticed worse response time on a z/9 with Driver 67 than one with Driver 63. Thanks, Chris Burgess EMC² where information lives Phone: 1-800-445-2588 x42149 1-508-249-2149 Pager: 1-877-443-8447 Fax: 1-508-544-2076 Email: [EMAIL PROTECTED] -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Jim Mulder Sent: Wednesday, October 10, 2007 11:20 PM To: [email protected] Subject: Re: Logical to Physical CPU ratio ROT (was Re: IXC454I messages) IBM Mainframe Discussion List <[email protected]> wrote on 10/10/2007 08:40:02 PM: > The SAD screen, for the CP's, showed some spikes up around 60% as the > other LPARs came up. Not sure what to make of LPAR utilization for it > seems to always show 100%. > First, make sure you have PTFs installed for APARs OA18452, OA18348, OA15188 If you are then still seeing really high physical CP utilization when the MVS LPARs aren't running any workload, you could experiment with specifying SHORTWAITMIN=1000 or SHORTWAITMIN=2000 in your IEAOPTxx That's an undocumented parameter, so I'm not going to talk a lot about what it means here. The situations where I have seen it to be helpful usually involve a lot of IPLed but idle MVS LPARs on a machine which has a lot of physical CPs. Jim Mulder z/OS System Test IBM Corp. Poughkeepsie, NY > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On > Behalf Of Jim Mulder > Sent: Wednesday, October 10, 2007 8:33 PM > To: [email protected] > Subject: Re: Logical to Physical CPU ratio ROT (was Re: IXC454I > messages) > > IBM Mainframe Discussion List <[email protected]> wrote on > 10/10/2007 > > 07:48:26 PM: > > > Just out of curiosity, look at the System Activity Display (SAD, or > whatever it is called on these machines) on the SE or HMC, and see > what the physical CP utilization looks like while this is going on. ---------------------------------------------------------------------- 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 This e-mail may contain confidential or privileged information. If you think you have received this e-mail in error, please advise the sender by reply e-mail and then delete this e-mail immediately. Thank you. Aetna ---------------------------------------------------------------------- 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
