Let's help a little further. Server side aborts really are not something that is done. You are playing with a live database that is ever changing with the thousands of users communicating with it. So, BOINC has a timeout feature which would have been used and it would have been left at that.
As for what happened in your reading of the task:
<stderr_txt> is a header (opener) tag
</stderr_txt> is a footer (closer) tag
These are on all tasks and could be better named, but have been a standard for for BOINC and their science theory calculations, it just means the start and end of the erroneous output of the information that was gathered during the calculations.
Hope this helps some.
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