We are just migrating our BI Database (2005) over to a new 2012 Server.
A backup of the BI Database has been restored onto the 2012 database.
The database uses a linked server to being back data from the source system (ERP), they are both pulling back data against the same system the OLD BI Server with far last resource performs the nightly load quicker than on the new server.
I have done some tests to see where the hold up is, and isolated one query that is a bottleneck for the new server, the query itself is bringing back 5 million records.
When running the query on the old server it takes 4 minutes and 21s on the new server it takes 4 mins and 41s to pull back the records.
The inserts which area a insert INTO Select on the OLD BI Server take 4:41 and on the new BI Server take 45 minutes.
The tables are identical and have taken off the index on the PK on the new server but has no impact on performance.
Any suggestions on why the new BI Server which has far greater resource is taking over 40 minutes longer.
Am I right in thinking this could be a IO with the discs?
I'm no expert on hardware, but since no one else has replied, here's a basic suggestion - check the Power Options on the new server. The power plan may be throttling your CPU to conserve energy.
Also, what do you mean you have "taken off the index on the PK on the new server"? If you have defined a PK, there will be an index to support it. If you've removed the PK, the table is now a heap. If your load process uses joins, MERGE joins, correlated subqueries, etc. that rely on the PK, removing the PK will have a disastrous effect on performance.
If you need more help, we'll need more details - for starters, the INSERT query and the execution plans from both the old server and the new server. This article
explains what information will be needed, how to get it, and how to post it.