how to start archive immediately

Got some questions with archiving mails.

1. I use the command "Start-ManagedFolderAssistant" to archive my mailbox immediately. But nothing happened.

I found an article: http://technet.microsoft.com/en-us/library/dd297955(v=exchg.150).aspx

it mentioned the Managed Folder Assistant is a throttle-based engine, does that mean we have to wait until the tasks in server are all clear?

If so, how can we clear the process by ourselves?

2. If the system is a throttle-based engine, does that mean that the assistant are always running? How about the 7-days cycle this article mentioned? 

http://help.outlook.com/en-us/140/gg271153.aspx 

3. Sometimes the archiving process just paused, even there are still mails left in my Inbox. Is there any limitation with archive policy?

Thanks !