We just got our new 32-core server to get SQL 2012 installed on it. Coming from a 16-core SQL 2008 server, our expectations were high.
BUT, turned out that results of our first set of performance tests were not what we expected.
After some investigations at system level we found that the server had 4 NUMA nodes but one was only hosting 4 schedulers, one was even OFFLINE.
Turns out that we installed SQL Server 2012 with a SKU that is limited to 20 cores. The errorlog stated clearly ‘…using 20 logical processors based on SQL Server licensing.…’
So we need a licence upgrade.
Many thanks to Jonathan Kehayias for pointing this out for us.
More info in a blogpost from Aaron Bertrand (http://sqlblog.com/blogs/aaron_bertrand/archive/2012/04/27/a-cautionary-tale-about-grandfathering-CAL-licenses-in-SQL-Server-2012-Enterprise.aspx