Jan, "Overhead" gives the impression of useless, wasted CPU time, but "management" time often gives the same impression ;-)
Kees. -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Jan Vanbrabant Sent: Tuesday, February 26, 2013 11:06 To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: ''MVS overhead'' (as indicated by OMEGAMON) Thanks to you all for your thoughts and good advice so far!* * Horst, *Re. you saying: (IMHO the term "overhead" is misleading, 'management time' would be more accurate).* What do you mean by this? Simply stated: overhead is all wat is NOT 'captured' on some application or sw component. LPAR Mgt time for example *is* reported. So, what are you having in mind? Work Load Mgr ? (your beloved 'baby' ;-) ) Jan On Thu, Feb 21, 2013 at 5:21 PM, Horst Sinram <sin...@de.ibm.com> wrote: > Jan, > > it appears the monitor is trying to tell you that you have a low > "capture ratio". Searching for that term should give you a good > understanding of what the message really means, and in a lot of good > advice, e.g. in the "Effective zSeries Performance Monitoring Using > Resource Measurement Facility" publication. (IMHO the term "overhead" > is misleading, 'management time' would be more accurate). > If you believe there might be a problem you may want to start with > verifying LPAR configuration and IEAOPTxx settings (any obscure timing > parameters? Anything violating recommendations?). You could also > verify that the capture ratio is indeed low using SMF70/72 data. > > Phantom weight is irrelevant in this context. It is only a vehicle to > tell PR/SM how to cap the partition. The fact that the LPAR *is* > capped at that time (to what extent?) may very well be relevant, > though: More work, longer work queues... > CPUMF counters won't help you diagnosing anything. CPUMF sampling > could help -theoretically- but the data may be very hard to evaluate. > > Horst Sinram - IBM z/OS Workload Management > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, send > email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ******************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ******************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
