11 million rows shouldn't be such a problem. I would do a direct load through a db link. You can do this by using the APPEND hint. Here's how I would do this.
1. Create the table (no indexes or primary key) with no rows in database B
2. Create the db link in database B
3. use an insert statement like this:
insert /*+ APPEND */ into tableA (select * from tableA@databaseA);
This will bybass the undo/redo writing. You'll be amazed at the load time. I use this all the time and load about 4 million rows in 20 seconds. Remember to build the indexes/primary key after you load the table.
Arm yourself with knowledge