Re: Odd locked file behavior - Any assistance greatly appreciated

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Sorry, can't help with the document. Surely it depend what file locking
method you use. If you are absolutely sure that they Move the file While you
have it Locked, that is a failure of the locking mechanism, isn't it? You
would have to check at exactly what stage of Your process the file is being
moved, and whether it is supposed to be locked at that point or not. I
suppose Filemon might tell you exactly what is going on with the file, if
you could catch it in action,
Anthony


"Allen C." <AllenC@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:DC5292AA-EF53-48F3-BF93-F3189F8983AD@xxxxxxxxxxxxxxxx
Anthony,

Thank you for the quick response. I've sent an email to our developers
confirming they lock the output files we are creating for exclusive use.
I
also wanted to give you some additional background information. We have
no
control over the Java application that our customer wrote to pick up the
files. We requested that they use our triggers but instead they decided
just
issuing a file move command would be sufficient. What I've been trying to
figure out is how could a move command impact a file that our application
is
building and is suppose to have exclusive control over? With that
information (known issue/white paper/etc) I could go back to our customer
and
force them to start using our trigger files. Right now it is just our
word
(saying your move command is negatively impacting our file) and them
saying
(no, it is not).

I've worked with data mover applications for years and I've never seen one
using the logic, "I'll just issue a Move command. If the file isn't ready
I'll get an error and will just wait a bit longer." All that I have seen
either use a trigger/catalog file or monitor a file for growth over a
period
of time.

"Anthony" wrote:
It just seems like a defective process at a basic level. I'm not sure
what
document would describe it. How could the java app know that the file is
complete and that you are not about to start writing some more data to
it,
unless it read the contents and applied some logic to say the file was
valid
and complete - which is what your trigger does? You would have to either
lock the file for exclusive use until it was ready, in your app, or
signal
to the java app that a new file was available when you app has finished
writing the file.
Anthony


"Allen C." <AllenC@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:3F7014C9-2DA0-4EB1-9459-7AC1BF16F4F3@xxxxxxxxxxxxxxxx
I'll try to be as brief as possible. I have an application installed
at
one
of our customer sites. The application creates data files (with
trigger
files) to feed other systems. Our customer has written a Java based
application to move these export files from our application server to
another
system. The Java application doesn't monitor for our trigger file
instead
monitoring for a file to be created. Once the file appears in the file
system their Java application attempts to move the file. Their thought
process is that if we are creating/modifying the file then it will be
locked
so the Java app will not be able to process the file so it will in turn
wait
until a later time and try again. We are periodically running into a
problem
where our output file is truncated. Reviewing our log files indicate
that
we
loose access (write/close/etc) to the file. My suspicion is that when
their
Java application makes a request to move the file just prior to our
application writing to the file that it is causing the contention. I
would
be grateful if anyone can confirm my suspicions and point me to a
technical
article that I can forward to them so that they will modify their
process.

Thank you in advance.
Allen






.

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