release

# File activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb, line 427
      def release(conn)
        thread_id = if @reserved_connections[current_connection_id] == conn
          current_connection_id
        else
          @reserved_connections.keys.find { |k|
            @reserved_connections[k] == conn
          }
        end

        @reserved_connections.delete thread_id if thread_id
      end