We use a permanent maintenance volume that isn’t generally IPL’d from. I triple the space and increase dirblks and use no secondaries. We use mod 27s and could use mod 54s if needed. So space isn’t an issue for me. That res is copied to the other systems during rollout.
On Thu, Sep 22, 2022 at 3:13 PM Mark Zelden <[email protected]> wrote: > On Thu, 22 Sep 2022 13:49:50 -0500, Carmen Vitullo <[email protected]> > wrote: > > >I've been doing this on my ServerPac for a while, I've even called out > >the ServerPac folks about the issue of, why deliver linklist lpalist > >datasets with secondary allocation if the linkist does not support it, > > Secondary extents are certainly supported in the LNKLST. What you can't > do is > take a secondary to the "live" LNKLST for a PDS, but you can for PDSE and > pick up the change with an LLA REFRESH or UPDATE. For LPA libs it doesn't > matter ever since that is only read in at IPL time. > > The number of extents in the LNKLST used to be a problem for some systems, > but when > the rules changed in DFSMS/MVS 1.3 to be "255 total extents or less" with > PDSE always > counting as 1 extent, that helped a lot. I personally want secondary > extents, at > least for some data sets to support applying maintenance. I always run > SMP/E apply > with COMPRESS(ALL) anyway so it's not going to continually increase and > I'd rather > get a secondary on a few libraries than have the apply blow up, have > allocate a new > larger DSN, copy old to new, rename and restart my apply. I'm pretty sure > this is > why ServerPac allocations came with secondary extents going back in > history. > > Due to 3390-9s geometry being my main sysres volume still, over allocation > from ServerPac (or now z/OSMF) has been more of a problem for me than > under allocation, so when building my local maintenance sysres after > install I have > had to free space on some larger PDS or PDSE files to get everything to > fit and > have spare space on the sysres for maintenance. Then if something takes a > secondary during apply, I don't care. The prod LNKLSTs have secondaries on > some data sets on the sysres, but again I don't care. No one better be > updating > the live sysres anyway except under extreme circumstances. > > As usual YMMV and if you are in a shop with 220 LNKLST data sets you > probably > have a very good reason for never wanting any secondary extents even in > your > maintenance environment. > > > Best Regards, > > Mark > -- > Mark Zelden - Zelden Consulting Services - z/OS, OS/390 and MVS > ITIL v3 Foundation Certified > mailto:[email protected] > Mark's MVS Utilities: http://www.mzelden.com/mvsutil.html > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > -- Michael Babcock OneMain Financial z/OS Systems Programmer, Lead ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
