I believe that I have seen an 'under load' effect when trying to manage low use LPARs. Consider an LPAR that loafs along slurping a mere 3 MUS's and that is quite enough for its mission. But if I soft cap that LPAR at, say, 4, and it spikes to, say 10, then the cap is hit within an interval or two.
Compare to an LPAR gulping 20 or so and then spiking to 100. It takes that LPAR a considerable time for the rolling average to climb to a cap of, say, 80. Now this is just a perception and I have not done any measurements but it is something I think about as I evaluate candidate hard capping and soft capping values. Perhaps one of the math whizzes on the forum could comment. -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Al Sherkow Sent: Tuesday, December 30, 2008 10:47 AM To: [email protected] Subject: Re: Need to cap my software costs You are correct that you do not have LPAR Group Capacity limits with z/OS 1.7. You can cap those small LPARs but you must use a soft cap on the 'most loved LPAR' also. Otherwise that will drive the box to 100% (if there is workload that wants that capacity). The max 4HRA for invoicing is simultaneous across the LPARs within any hour. The limit of this number is the sum of the defined capacities. You might want to both hard cap and soft cap the small LPARs. Al Sherkow, I/S Management Strategies, Ltd. Consulting Expertise on Capacity Planning, Performance Tuning, WLC, LPARs, IRD and LCS Software Seminars on IBM SW Pricing, LPARs, and IRD Voice: +1 414 332-3062 Web: www.sherkow.com ---------------------------------------------------------------------- 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 NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. ---------------------------------------------------------------------- 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
