No Subject

This is a reply to Peter O'Connor's warning about the impact that
compressed objects can have on your estimates both for downtime
and for disk space usage when upgrading AS/400 from CISC to RISC.

Peter is correct in his warning.  Compressed objects DO need to be
considered during planning.  IBM recognized the importance of compressed
objects and included them as a category in the "unsupported objects"
report for Enhanced Upgrade Assistant.  Each object type that is
listed in the "unsupported objects" display and report has help text
associated with it.  Chapter 5 of the Road Map includes a table called
"Solutions for Potential Software Problems" that addresses each object
type that appears on the "unsupported objects" report.  The entry for
compressed objects says "You have used the Compress Object command to
compress objects and conserve disk storage.  However, when your target
system converts program objects, it must decompress them.  Enhanced
Upgrade Assistant estimates of objects conversion time and required disk
storage will not be accurate if you have compressed objects on your
current system."

The alternatives column in the table suggests the following:
"1. Decompress the objects.  Rerun the STRUPGPRP *OBJ command.  Then
 rerun the options to estimate disk storage requirments and
 upgrade timings.

 2. Make sure that you have sufficient time and working space for
 object conversion on your target system.  Plan your object
 conversion carefully to allow for object decompression."

We think that this adequately and visibly addresses the potential
problem for customers who carefully follow the Road Map's guidance.
However, we certainly appreciate Peter's additional warning since
this is an area that has caused problems in the past.  I would add
one caveat to Peter's suggestions.  If you have a large number of
compressed objects on your system, it might be because your disk
capacity is at a premium.  Decompressing all objects at the same
time might not be an option for you.  You might need to decompress
and recompress library by library and manually adjust your disk
space and timing estimates.  This will be very time-consuming, but
without adequate disk space, it might be your only option.

Submitted by Jelan Heidelberg, AS/400 Division,
co-author of AS/400 Road Map for Changing to PowerPC Technology
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