It happens very rare and with different records, no matter if a set the thread count to 10 or to 100. I looked through the log and found no other threads trying to change the file pointer. Do you have any idea of what can be wrong?
Man I don't know the Urly Bird spec but the problem that you mention seems to be a field length problem. I had a problem as yours on my project, I wasn't counting the first byt that indicates the total length, So sometimes my updates and selects came like yours are coming.
Well, it's just a wondering.... Try to log even more details and post here...
Hope you found this problem soon, wish you lucky
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