stenotype sometimes doesn't shut down when it gets SIGINT/SIGTERM signals about stenographer HOT 3 CLOSED

This appears to be stuck waiting for index writer threads to finish, but they never do. Those threads appear to be blocking on the producer/consumer queue waiting for a new file to write... they didn't get the NULL we sent? Might try to rewrite ProducerConsumerQueue with an explicit Close() to shut it down.

from stenographer.

Tracked this down, I think, to thread::join on the RunThread threads not returning.

from stenographer.

So the final determination was a deadlock in the packet reading/writing threads, which caused a deadlock in the PacketsV3 destructor. This means that the main thread was stuck waiting on the thread::joins for RunThread, but that the final LOG message in RunThread had already been written. So the "stuck index writers" were a red herring... the main thread hadn't gotten to the point where it could write its NULLs to stop them.

from stenographer.