The normal application dumps are normal business.

Once you know how to handle this - and you learn it best by teaching or
mentoring others - you can of course go further and solve more advanced
problems. A very hard problem for me was a race condition with two
subtasks in IBM's APL code (the linkage to other languages, processor 11).
It took me weeks to convince IBM that the error is in their code, not in
ours,
because they couldn't reproduce it on their machines (our machines were
faster, more CPUs). They accepted it in the end when I did a local fix
to their code and
documented in detail, what I made - I simply checked the ECB, and when
finding the condition that would lead to the subsequent ABEND, I waited for
a little amount of time, wrote a message, and then tried it again - and so
the error disappeared. But it took me weeks to find the reason for the
problems
and to understand the code at the relevant positions - of course, it's
all OCO.

IBM's APL code was patched on the fly, after initial load - control was
transferred from the original WAIT / POST routine to one of my own,
that worked a little bit different, see above.

In the end, IBM accepted my proposition for the remedy of this problem.

While working on this episode, it was very important for me that there
was a co-worker who was very experienced with all the z/OS topics
and who encouraged me to continue. He said to me things like that he
already experienced problems with APL in this particular area and he
talked with me about my different approaches and, although he did not
support me with practical work, the discussions with him were very helpful
to me. Also some SLIP traces, because, as you can imagine, the problem
only occured once for some millions of transactions, only during periods
of peak load.

Kind regards

Bernd



Am 30.07.2013 18:13, schrieb John Gilmore:
There is no substitute for experience in the company of mentors/more
knowledgeable colleagues.  For this reason the very experienced,
sure-footed mules who carry people down into and back up out of the
Grand Canyon of the Colorado should not be consulted about the
Canyon's geology.

To vary the metaphor, books having titles like 'Topology made easy' or
'Neurosurgery for dummies' achieve their objectives, when they do, by
leaving the hard parts out.

John Gilmore, Ashland, MA 01721 - USA

Reply via email to