Not conclusive yet, as the client's only been running about three days, but it looks as though this simple fix solved the problem.

The answer seems to be that Thread::Semaphore is, ironically, not thread-safe.

In reply to Re^3: Semaphores failing to prevent race condition by Llew_Llaw_Gyffes
in thread Semaphores failing to prevent race condition by Llew_Llaw_Gyffes

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