Some even more helpful information would be the end of stderr (/Library/Application Support/BOINC Data/slots/*/stderr.txt) of the task while it is stuck, and especially whether the output changes (it might be that just the display of progress is broken). And I would be really thankful for a Shark tree (shark is a performance analysis tool that is installed with Xcode or CHUD tools) to see what function keeps the CPU busy without progress.
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Some recent change causes OSX 10.9 on PPC4 to hang in a system c
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BTW: Probably VTune could do the same on Linux and Windows for "stuck" tasks. All current Apps are compiled with debugging symbols.
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RE: Not sure (my evaluation
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For the 4.33 the PDB is distributed withe the App again.
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