System zEC12 CFLEVEL 18 RMF Instrumentation Improvements
MartinPacker 11000094DH Visits (4447)
I don't know how many of you will've spotted this but there was a nice instrumentation enhancement in the recent System zEC12 announcement.
It comes with the RMF support for CFLEVEL 18 (OA37826 and provides much more detail on paths to Coupling Facilities (CFs).
Previously RMF reported channel path acronyms - one per path. And that was all. (A channel path acronym is something like "CIB" for "Infiniband".) Those of you who know something about Coupling Facility link technology will recognise there are multiple types of Infiniband link now. If you do you'll equally recognise other deficiencies in the RMF topology information. This support fills in many of the gaps.
(Note: The existing support covers not only paths between z/OS LPARs and CFs but also between CFs - in support of structure duplexing.)
Though my personal interest is in the enhancements to the SMF Type 74 Subtype 4 record cut by RMF, there are corresponding enhancements to RMF Monitor III and the RMF Postprocessor.
So, what do we have?
The above is all topology information. What we don't have is traffic over the paths. Personally I think I'd like to see it for two reasons:
If you agree that traffic and error analysis would be something you'd value let me know. Alternatively, if you think it's a dumb idea let me know (gently).
The new information is available for both z/OS-to-CF and CF-to-CF links. The only difference between the two is the "anchor" in the Local Coupling Facility and Remote Coupling Facility sections.
There is some performance information, which I think is useful:
Most of the information in the SMF record is in a new section (Channel Path Data Section) - which is going to cause mass bustage of my code. (Actually I don't handle Remote Coupling Facility sections terribly well so some reworking of my code is overdue anyway.) Fortunately the lab sent me a pretty complex set of data - so if I'm quiet you'll know I'm 'heads down' in my code.
And I'm looking forward to seeing data from real customers: If you're at z/OS RMF Release 12 or 13 you can install the PTFs and take advantage of the new stuff too.