Do not clean up from persistent_term, closes #342

Author: josevalim

lib/broadway/topology.ex

@@ -91,9 +91,14 @@ defmodule Broadway.Topology do
     ref = Process.monitor(supervisor_pid)
     Process.exit(supervisor_pid, reason_to_signal(reason))
 
-    receive do
-      {:DOWN, ^ref, _, _, _} -> :persistent_term.erase({Broadway, name})
-    end
+    # We don't delete from persistent term on purpose. Since the process is
+    # named, we can assume it does not start dynamically, so it will either
+    # restart or the amount of memory it uses is negligibla to justify the
+    # process purging done by persistent_term. If the repo is restarted and
+    # stores the same metadata, then no purging happens either.
+    # receive do
+    #   {:DOWN, ^ref, _, _, _} -> :persistent_term.erase({Broadway, name})
+    # end
 
     :ok
   end