On 6/28/2012 7:02 AM, Jay Toran wrote:
If the module is above the line, my code that the macro calls doesn't run.
I want to give the programmer a warning if that could happen by letting them
know at assemble time.
If it isn't possible, any ideas?
When presented with a similar challenge many years ago, we decided to invest the
development resources necessary to make ALL programs RMODE(31).
Surprisingly, 24-bit VSCR is as important today as when MVS/XA first arrived on
the scene. It's not a problem that was 'solved' decades ago and can now be
ignored. The number of logical processors per LPAR is growing as is the number
of concurrent address spaces supported by z/OS and other operating systems. This
'horizontal' growth is putting new pressure on virtual and (precious real)
memory below 16MB.
For example, if a z/OS system is now capable of running 1000 more address spaces
than it could twenty years ago, that means 384,000 additional bytes of fixed,
common storage below 16MB is required just to hold the ASCBs (address space
control blocks -- 384 bytes each)! There are other fixed, common storage control
blocks needed as well. And 24-bit common storage, whether fixed or not, reduces
the amount of 24-bit virtual private area available.
IMHO, any programs that still do I/O to buffers below the line should be
modified to do I/O to buffers above the line as soon as possible. (Even if you
think your RMODE(24) program does no I/O, consider that below-the-line I/O
occurs in CSV FETCH processing just to load your RMODE(24) program into memory!)
Of course, the goal should be RMODE(31) for all programs if practical to do so.
That should get you positioned just in time for entry into the world of
RMODE(64) programming when/if such a thing comes to be reality. :-)
--
Edward E Jaffe
Phoenix Software International, Inc
831 Parkview Drive North
El Segundo, CA 90245
310-338-0400 x318
[email protected]
http://www.phoenixsoftware.com/
