Thanks Allan, Koehler &Engelbrecht. We are using z/OS 1.13 and we already pulled the RMF report and many of jobs are long running and for sample I have list couple of them.
During the Batch window only its rising to 100% and remaining time its normal. We made analysis on STS's, Network, Tape, TSO & Jobs and only the Batch job is making to reach high CPU %. Regards, Vinoth M -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Staller, Allan Sent: Thursday, September 18, 2014 6:27 PM To: [email protected] Subject: Re: High CPU Utilized High CPU utilization is not (by itself) a problem. OS/MVT (and all of its successors, OS/MVS, MVS/ESA, OS/390. z/OS..) have been designed (and redesigned) to run at 100% utilization for months and years at a time (I know, I have been there). That being said, most things will run (FSVO) better when there is a little excess capacity. There are so many variables that can contribute to elapsed time that I can't even begin to provide any sort of meaningful discussion about any of them. A partial list of things to look at: PR/SM overhead (too many logical processors defined) Workload manager policy Device contention DFHSM (or equivalent) recall Virtual Tape recall Human factors (physical tape mounting) Job Scheduling Job Contention And many more... One key to look at is the RMF Mon I CPU report. The key number is the "IN READY" queue. The ideal number is (number of logical processors * 1). That is, one job is always ready to execute. IN READY < 1 indicates excess CPU capacity IN READY > 1 indicates excessive workload (FSVO excessive). There is no Rule of Thumb here. Whatever you can tolerate is a good number As other have said, are SLA's being missed? HTH, <snip> In environment we are using 2818-X02 box with around 1100 MIPS and this boxes is utilized by couple of LPARS(SYSP & SYST). One is a PROD and other is Play LPAR and almost 90% of weight is contributed to PROD SYSP system. We have a scenario of High CPU utilized only during our batch window(4hours) and few days back the system was recycled due to the high CPU utilized and we feel that this may create impact during Peak season in November, December. Also we got a report from our batch team and most of batch jobs are using more CPU time with very high elapsed time and below is for your ref. JOB NAME CPU TIME ELAPSED TIME Job A 29:22.1 01.48.26.24 Job B 19:12.3 02.44.26.24 We are position to bring down the CPU Utilization time and make the system healthy and we are trying to split the Batch jobs and run on different time. I would like to get some clarity on the Elapsed time, whether this elapsed will make use of the CPU and will it be the cause of high CPU utilized during batch window? </snip> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
