For Day 7, I want to talk about one specific Intel processor series that I highly recommend that you do not use for SQL Server 2012 workloads. This processor is the 45nm Intel Xeon 7400 Series, which was released in Q3 of 2008. There were seven specific models in this series, based on the Penryn Core2 microarchitecture, culminating in the Intel Xeon X7460 processor.
At the time of it’s initial release, this was a very good processor. It has a base clock speed of 2.66GHz, with six physical cores, which allowed you to have 24 physical cores in a four-socket server (such as a Dell PowerEdge R900), along with up to 256GB of RAM. This sounds impressive, but there are some fundamental issues with this processor by modern standards.
I can remember unsuccessfully begging my CTO at NewsGator to let me buy one of these during the late-2008 to mid-2009 time-frame. That was one battle I lost (which was actually a good thing in hindsight), but I was later able to get something much better.
The Intel Xeon 7400 series was the last four-socket capable Intel processor to use the older symmetric multiprocessing (SMP) architecture instead of the more modern non-uniform memory access (NUMA) architecture. This means that it is hobbled by the limitations of the old front-side bus, where all of the processors in a system use the same shared pathway to main memory. This causes increasing contention and performance bottlenecks as the number processors in a system increases.
The Xeon 7400 series has a relatively high number of physical cores that have fairly low single-threaded performance by modern standards. It also does not have Intel hyper-threading or Turbo Boost technology. This means that it is fairly expensive to purchase licenses for SQL Server 2012 Enterprise Edition, for a system that will have poor performance compared to a brand new system.
Here is an example from the TPC-E OLTP benchmark. There was a Dell R900 system with four Xeon X7460 processors with a TPC-E score of 671.35. Dividing that score by 24 physical cores gives us a result of 27.97 per core. There is a new HP Proliant DL380p Gen 8 system with two Xeon E5-2690 processors with a TPC-E score of 1881.76. Dividing that score by 16 physical cores gives us a result of 117.61 per core, which is 4.2 times higher than the old system.
The old system would require (24) SQL Server 2012 Enterprise Edition core licenses, which have a retail cost of $6872.00 each. That would be $164,928.00 for the licenses required for the entire system. The new system would require only (16) SQL Server 2012 Enterprise Edition core licenses, which would cost $109,952.00 for the entire system.
Reusing that old server for SQL Server 2012 would cost 50% more, to get about 1/4th of the OLTP performance. That seems like a pretty bad choice to me. Many organizations still have systems running with that processor, since it is not really that old yet. When it becomes time to upgrade to SQL Server 2012, do not make the mistake of reusing your existing hardware. You will get much lower performance and scalability, and potentially pay much higher SQL Server licensing costs.