Check SMF99 subtype 5 for storage target. SRM manages to a storage target which is set in a complex way if you are not using storage critical, but aims to keep interactive work responsive. Your CICS regions may be mis-categorized for this purpose. This storage target is enforced pre-emptively (even when there isn't a system-wide storage shortage yet), which is of course why this way of managing CICS regions has been replaced by storage critical.
On Fri, Oct 9, 2015 at 10:34 PM, Peter Hunkeler <p...@gmx.ch> wrote: > A word in advance: I have subscribed to the MXG-L list but have not yet > granted access, so I'm asking here first. > > > > I'm busy working on a problem some of CICS region are suffering from > periodically. There are times when some CICS regions are paging-in some MB > of storage and are thus suffering from the paging delay. > > > Since this is about page-in, the storage that is paged-out has been in use > before. It is not too clear yet what this storage is and what is causing it > to be referenced again in that massive way. That's being investigated and > is not directly my question here, although any hint is welcome as well. > > > I'm trying to understand why that amount of storage has been paged-out > from those CICS regions, and when this has happened. looking at the SMF30 > subtype 2 for the CICS regions a indeed can see intervals with large number > of pages being paged-out (SMF30PGO). I do not see any non-zero values > indicating pages had been stolen (SMF30PST). > > > > It has been my understanding (which may be wrong, of course) that page > steaqling happens when the Available Frame Queue goes below the min > threshold. SRM/RSM will them steal pages and page them out. I would expect > those numbers to appear in SMF30PST. And if this number is 0 for an address > space, this one was not a donor in a low AFQ situation, right? > > > > > We do see the AFQ going low sometimes, and it was my assumption that those > CICSs were victims by having pages stolen. This does not seem to be the > case. What then causes the pages to be paged-out (SMF30PGO)? Is CICS doing > PGOUT by itself? > > > > > > > -- > Peter Hunkeler > > > > > > > > > > -- > Peter Hunkeler > > ---------------------------------------------------------------------- > 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
