So I am working with an inherited SQL query that queries 8 different tables. 5 of which have over a million records. 
I have 3 different servers. 

Server 1, Server 2 and Server 3. They all have the same data/tables/structure across all servers. 
Server 3 has an Iris database engine and the other 2 are Cache 2015.1.4.
I have a problem with views and performance across the servers being inconsistent. 
Thankfully Server 1 is the current live server that performs "fast enough".
Server 2 is being synced from Server 1 and acts as a report server.

And Server 3 is supposedly a new Live server.