I'm using the Teradata provider built into TDP. I presume it's Teradata.net, but I don't see anything specifying either way. I also use SQL Assistant (Teradata's query tool) and its Teradata.net provider and that is blazing fast.
I played around with the Response Buffer Size but that didn't do anything. The weird thing I just noticed is that the first time I hit a table, it takes about 5-10 minutes to complete the query, but successive queries only on that table take 1-2 seconds. If I try another table on the same database, it will take 5-10 minutes. But then successive queries are fast. I then go back to table 1 and it is still fast.
As an example, a series of queries and the time each one takes:
1) select * from database1.table111 : 5 minutes
2) select * from database1.table111 : 10 seconds
3) select * from database1.table222 : 5 minutes
4) select * from database1.table222 : 10 seconds
5) select * from database1.table111 : 10 seconds
6) select *from database1.table333 : 5 minutes
7) select * from database1.table333 : 10 seconds
8) select * from database1.table222 : 10 seconds
9) select * from database1.table111 : 10 seconds
On the long queries, I hit F5 and the UI freezes for about 5 minutes, then it starts to respond and loads the data into the results pane within a few seconds. On the fast queries, the UI responds immediately to F5 and almost instantly begins to load the data into the results pane.
It doesn't seem to be a database problem since queries are fine once the connection is established. It's like TDP is opening a new connection for each table it hits, and that new connection process takes way longer than it should.