On 27-Mar-2014 06:21 -0700, Steinmetz, Paul wrote:
I saw a disk savings of 2%, or 58 gb.
My V7R1 LPAR is smaller than my V6R1 LPAR
So as I infer: An LPAR that was at v6r1, was upgraded to v7r1, using
the DSLO, and now the overall storage on the since-upgraded LPAR
requires 2% less space.
A followup reply had suggested that "I actually did NOT permanent
apply the V6R1 PTFs."
Seems likely that the storage from the excess, effectively duplicate
OS code [i.e. two copies of each program as part of a PTF, many of the
copies being created from a different revision level of the source code]
that remained on the v6r1 partition were deleted as part of the upgrade
rather than as part of the pre-upgrade processing. Probably a good
portion of that 2% gain would have been achieved while on v6r1 if the
perm apply processing had been done there.
Another thing, is that the code from media should have been
/compressed/ and remain compressed for some time since the install
completes. Thus had the v6r1 system been up and running for some time
and actively being used, the various OS objects likely had since been
decompressed on that release. The newly installed v7r1 with compressed
objects would slowly decompress those same objects over time, and any
portion of the storage gain from those compressed objects would be
getting pared down over that same period of time.
FWiW: I actually can not recall how the OS deals with those PTFs that
were not permanently applied, but I expect they would have been
processed by the upgrade similarly to what the perm apply would have
effected, even if not updating the PTF database to reflect the effect.
The OS could, to get back much of the excess storage, effect blindly,
each of DLTPGM QSYS/QPZ* and DLTSRVPGM QSYS/QPZ*; i.e. even deleting the
OS objects with that same naming convention would be little harm,
because the restore for install would get all necessary code onto the
system from the media. Any previous-release PTFed programs are wholly
unnecessary for the operation of the new OS, so their loss is of no
consequence to the newly installed OS.
FWiW: Might be worth reviewing the history log and SCPF joblog from
the install for various "deleted" messages, to see if anything
unexpected was deleted during the install. If for example one of the
larger system database cross-reference files was deleted due to an error
:-( then that could /recover/ a notable amount of storage, but the
effect would be temporary, pending the condition being recovered by a
reclaim of the *DBXREF.