I find that hard to believe - but I will include an IO trace.

On Sun, 19 Jul 2015 09:26:05 -0500 John McKown <[email protected]>
wrote:

:>This is a pure guess on my part. I don't known how BPAM works internally.
:>But I do know that in a standard PDS, there are multiple entries in each
:>physical directory block record on disk. So I am wondering if what is
:>happening is that STOW reads __and buffers__ the directory block you're
:>working on, and then defers rewriting the directory block. This _might_
:>cause the 2nd job to have an out of date buffer for a physical directory
:>block record which happens to contain your old STOW data. When the 2nd job
:>gets around to flushing the data to disk, it would implicitly replace what
:>your 1st job had done in the directory.
:>
:>Just a WAG.
:>
:>On Sun, Jul 19, 2015 at 8:07 AM, Binyamin Dissen <[email protected]
:>> wrote:
:>
:>> I have code that does the following: (against a standard PDS)
:>>
:>>          ENQ
:>>          OPEN
:>>          BLDL
:>>          POINT TTR
:>>          READ
:>>          CHECK
:>>          WRITE  (in place)
:>>          CHECK
:>>          STOW R  (changing some directory info of the rewritten member))
:>>          CLOSE
:>>          DEQ
:>>
:>>
:>> When running single threaded, works fine.
:>>
:>> When running in multiple concurrent jobs, it appears that sometimes the
:>> STOW
:>> data is lost.
:>>
:>> GTF trace shows that the code is operating properly.
:>>
:>> What might II be missing?
:>>
:>> --
:>> Binyamin Dissen <[email protected]>
:>> http://www.dissensoftware.com
:>>
:>> Director, Dissen Software, Bar & Grill - Israel
:>>
:>>
:>> Should you use the mailblocks package and expect a response from me,
:>> you should preauthorize the dissensoftware.com domain.
:>>
:>> I very rarely bother responding to challenge/response systems,
:>> especially those from irresponsible companies.
:>>
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:>>

--
Binyamin Dissen <[email protected]>
http://www.dissensoftware.com

Director, Dissen Software, Bar & Grill - Israel


Should you use the mailblocks package and expect a response from me,
you should preauthorize the dissensoftware.com domain.

I very rarely bother responding to challenge/response systems,
especially those from irresponsible companies.

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