Feedback from my UKCMG Mainframe Performance Instrumentation Birds Of A Feather
MartinPacker 11000094DH Comment (1) Visits (4543)
It was a very good session, even if it was attended by just a "hard core" of mainframe sites. I think everyone said at least something and several said rather more than that. Here are some things I'd like to note from it...
There was a general feeling that it'd be useful to have a name for a machine that could be entered on the HMC and flow through to SMF records, particularly Type 70 (CPU). So for example a site might like to name it's machines "North Mainframe" and "South Mainframe" rather than just being identifiable by the hardware serial numbers 5112345 and 8356789. I think this is a really good idea - at least from MY perspective as someone who wanders onsite and would rather use the names YOU use for your machi nes, even if I do remember the serial numbers for at least one customer. :-) This idea, though, would require changes in at least three components. So I'm not overly optimistic. But I'll make some enquiries and see what we can do.
We also think that the serial number should appear in OTHER SMF records (than 70-1 and 74-4) such as the other RMF ones and also Type 30. That would allow much easier matching up.
On the memory front I didn't meet with that much interest - except that we think it important that the memory numbers become more accurate in Type 30 and Type 72. (Both of these are currently reported based on the notion of Service - which means that swappable workloads are under-reported in Type 72 and those that endure CPU queuing are under-reported in SMF 30.) We also would like to see SMF 70 report how big the machine's HSA is and how much memory is purchased but not assigned to a partition.
We discussed instrumentation for VLF / LLA and for Catalog - which we think could be improved.
When talking about techniques for managing SMF data the SMFUTIL tool was mentioned. I'll have to do some research into this, but I still think it worthwhile to post some examples of DFSORT being used to "slice and dice" SMF. One day. The meeting also felt that some kind of "best practices" guidance would be useful. Maybe I should start a wiki on the subject - so that the collective wisdom of the mainframe performance community can be tapped.
All in all I think the session was a success - and I'd like to do it again next year. I'll work on these items but, as I originally said, there are no guarantees.
So thanks to the participants. Plenty of food for thought.