document known bugs

BUGS

@@ -0,0 +1,24 @@
+Known bugs:
+
+1. Video formats suck
+---------------------
+One would expect video formats to allow for a wide range of tags. Things like
+writer, director, main actors, original author, etc. But most of them only
+provide ONE tag: title...
+Planned workaround: tag guessing (see TODO).
+
+2. Random hang
+--------------
+Something I encountered and don't understand: sometimes, seemingly randomly,
+the call to wait, to retrieve the exit status of a worker, does not return,
+though the worker *has* exited. This happens rarely, but it will probably hit
+you if you have more than 20.000 tasks to run. When this happens, just hit
+Control-C and re-run AtOM to resume transcoding.
+
+Symptoms:
+- Progress does not update anymore
+- a pstree only show one child process: sqlite3
+- strace()ing shows the script process stuck on waitpid()
+
+Please let me know if this hits you, or if you have any idea as to why this is
+happening and how to avoid it.