Is safe the events saved in forwarder's queue when the splunk receiver port closed?

[shizl]

I configure a port 9997 on a splunk server to receive a forwarder 's event. The forwarder will transfer all event continuously. I want to schedule a forwarder transfer.
I close the splunk receiver port at a special time and open at another special time,
The forwarder will be blocked when the port is closed. All events will enter a queue. maxQueueSize can configure the size of the queue. is it right?
Is safe the events saved in forwarder's queue?
Where the events is saved? memory or disk?
What is the performance of the forwarder when it is blocked.

[yannK]

By default the forwarder has a small memory queue, and will resent the events once an indexer is available.
If the forwarder is monitoring non volatile logs (i.e. not UDP) then it will pause the monitoring until the output is available.
But for the events already in memory, they can be lost if the forwarder is shut down.

FYI you can add persistent queues on disk
see http://docs.splunk.com/Documentation/Splunk/4.3.4/Data/Usepersistentqueues