<[EMAIL PROTECTED]> wrote in message
news:<OFD38D43EF.26E4669D-ON85257036.005F128B-85257036.005
[EMAIL PROTECTED]>...
> Ok, I'll be the whipping boy.
>
> Why can't the Operating System be "Enhanced" to intercept the Abend and
> close the files.
That's what module IFG0TC0A ("IFG-gotcha") does. It is an exit invoked
by task termination to process open files. However, there are problems
closing files as I mentioned before.
Most of the VSAM control blocks are in user key. If these have been
overlaid or incorrectly modified, writing this data to the catalog may
BREAK THE DATA SET. The effects of breaking the data set are much worse
than "throwing away" the data and verifying the data set on the next open.
No one wants an online application to have to recover a major data set and
be down for hours because it was broken closing it during an ABEND because
data was overlaid.
> Close any input file and/or VSAM file. There is already alot of
processing
> that occurs after
> the abend by building the dump thru Abend-Aid and other debuggers. We
> already have CICS
> with DTB feature that will backout changes and adds back to the last
> SYNCPOINT. DB2 can
> backout changes and adds back to the last COMMIT. So why can't Z/OS be
> changed to make sure that
> VSAM files are closed during Abend process ??
Because the only code at the moment is during task termination. As I
mentioned before, the access methods do NOT have recovery routines because
of the overhead and performance implications. Not that we're not trying to
solve that problem, but it's going to take quite a while to do it.
Movement of the control blocks into protected storage is a goal also, but
given the number of users/vendors/applications that try to touch these
blocks (and sometimes change them) means there are a lot of issues with
doing this. Not that we're not going to do it, but existing references by
programs will have to be changed.
So when CICS and/or DB2 recovery routines get entered, they can do backout,
etc. However control has been yanked away from the access method until
task termination processing, WAY after the application recovery routines
have been deleted.
Thanks,
Mark Thomen
Catalog/IDCAMS/VSAM Development
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