Yeah, the stuff I said there, plus... we see data from a lot of systems. Periodically I sample that data for interesting values, including what the SMF interval is. Historically that has been 15 minutes for right around 90% of the systems we see. Next most popular is 30 minutes in about 5% of the customers, although I actively discourage that when I see it. A few will show up with 5 or 10 minute intervals. And some customers will run with 1 minute intervals for all or part of the day.
It should be noted that on the creation side, the interval only drives the data storage required and the tiny bit of CPU/IO required to write those records. But of course when you go to process the data, having more intervals will mean that processing the data will take longer and consume more resources. That's usually the bigger concern. Opinion: In general, if I was running a system today, I'd probably use 5 minutes. Yes, it's 3x the data (vs 15 minutes), but for most systems that shouldn't really be a problem. And it may better align with your non-mainframe platforms. The 1 minute intervals are I think overkill, especially given the data you can get out of the SMF records that have shorter (sub-minute) intervals like the 99s and 98s. When you have 1 minute SMF intervals, you can generate a whole lot of SMF 30 interval records. And if you carry that forward to RMF/CMF, the 74s can get quite voluminous. I'm not saying 1 minute intervals are never useful, but that's a rather exceptional condition. Day-in, day-out most customers manage their systems just fine with 15 minute intervals, diving down to event or shorter interval records (like the 99s) as needed. Because everything has exceptions... one exception to my above thinking might be for certain customers with extreme spikes for important events. I believe I once saw a financial services customer that set a 1 minute interval for a few minutes around market open/close. That makes sense to me. The "we needed 1 minute intervals for a particular problem we had several years ago and just left it set to that" makes much less sense to me. Scott Chapman On Fri, 29 Dec 2023 17:35:56 -0800, Ed Jaffe <edja...@phoenixsoftware.com> wrote: >On 12/29/2023 3:20 PM, Mark Zelden wrote: >> This paper from Scott Chapman of EPS talks about the subject and he agrees >> with >> me that it should be no longer than 15 minutes and that RMF/SMF should be >> synced. >> >> https://www.pivotor.com/library/content/Chapman_SMFRecommendations_2022.pdf > >Super helpful. Thanks, Mark! > >-- >Phoenix Software International >Edward E. Jaffe >831 Parkview Drive North >El Segundo, CA 90245 >https://www.phoenixsoftware.com/ > > >-------------------------------------------------------------------------------- >This e-mail message, including any attachments, appended messages and the >information contained therein, is for the sole use of the intended >recipient(s). If you are not an intended recipient or have otherwise >received this email message in error, any use, dissemination, distribution, >review, storage or copying of this e-mail message and the information >contained therein is strictly prohibited. If you are not an intended >recipient, please contact the sender by reply e-mail and destroy all copies >of this email message and do not otherwise utilize or retain this email >message or any or all of the information contained therein. Although this >email message and any attachments or appended messages are believed to be >free of any virus or other defect that might affect any computer system into >which it is received and opened, it is the responsibility of the recipient >to ensure that it is virus free and no responsibility is accepted by the >sender for any loss or damage arising in any way from its opening or use. > >---------------------------------------------------------------------- >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
