For quite some time, I have been talking about how current Intel-based four-socket database servers have had significantly lower single-threaded processor performance than current Intel-based two-socket database servers. This is because the first generation Intel Xeon E7 processors were using the relatively old 32nm Westmere microarchitecture that was introduced in early 2011 for the initial Xeon E7 (Westmere-EX) product line.
These E7 processors also use much lower base and turbo clock speeds than current Xeon E5 v2 processors, which also hurts their single-threaded processor performance. They do have higher overall concurrent load capacity due to higher total memory capacity and more total processor cores, but the individual processor cores in most four-socket servers have been much slower than what you find in a modern two-socket server. Simply put, bigger servers are not faster servers. It is like comparing an eighteen wheeler truck to a Tesla Model S.
Now, that old assessment is going to change somewhat, with the release of the 22nm Intel Xeon E7 Processor v2 Family (Ivy Bridge-EX), and new model servers from the major server vendors that have even higher memory capacity, PCI-E 3.0 support, and 12Gbps SAS/SATA support, along with much faster RAID controllers. These processors are a substantial improvement over the previous generation 32nm Intel Xeon E7 processors (Westmere-EX) that have been available since early 2011.
It will still be possible to configure a new two-socket server, such as a Dell PowerEdge R720, with an appropriate 22nm Intel Xeon E5-2600 Processor v2 Family (Ivy Bridge-EP) processor that will have better single-threaded performance than a new four-socket server such as a Dell PowerEdge R920, but the gap will not be nearly as large as it once was.
The actual good news here for a database professional is the fact that you will be able to have a four-socket server that has as much load capacity as a previous generation, eight-socket server, that also performs nearly as well as a current two-socket server, while paying 25% less for your SQL Server 2012/2014 license costs (compared to a previous generation eight-socket server). This is a pretty big gift from Intel!
A more pessimistic view is that your SQL Server 2012/2014 license costs could rise by 50% as you move from an existing server equipped with four, ten-core Xeon E7-4870 processors (with a total of forty physical cores) to a new server with four, fifteen-core Xeon E7-4890 v2 processors (with a total of of sixty physical cores). For reasons known only to Intel, the lower core count SKUs in the Xeon E7-48xx v2 product family are not “frequency optimized”, meaning they do not have higher clock speeds than the high-end, E7-4890 v2 processor. The base and turbo clock speeds of the best lower core-count SKUs in the E7- 48xx v2 family actually drop off pretty quickly as the core counts go down. The shared-L3 cache sizes also drop off very quickly, as does the processor price, as you can see in Table 1.
| Processor | Physical Cores | L3 Cache | Base Clock | Turbo Clock | Price |
| E7-4890 v2 | 15 | 37.5 MB | 2.8GHz | 3.4GHz | $6,619.00 |
| E7-4860 v2 | 12 | 30 MB | 2.6GHz | 3.2GHz | $3,838.00 |
| E7-4830 v2 | 10 | 20 MB | 2.2GHz | 2.7GHz | $2,059.00 |
| E7-4820 v2 | 8 | 16 MB | 2.0GHz | 2.5GHz | $1,446.00 |
| E7-4809 v2 | 6 | 12 MB | 1.9GHz | N/A | $1,223.00 |
Table 1: Selected Intel E7-48xx v2 Processors
With the Xeon E4-48xx v2 product family, you are going to want to choose either the E7-4890 v2 or the E7-4860 v2 model processors in most situations, since the lower core count processors are giving up a substantial amount of performance due to their lower clock speeds and smaller L3 cache sizes. If you really want to reduce your core counts to reduce your SQL Server 2012/2014 license costs, you would be better off with the Intel Xeon E5-26xx v2 product family processors that are used in two socket servers. Another alternative is the upcoming Intel Xeon E5-46xx v2 product family processors that are used in four-socket servers.
Either of those choices would be better than one of the lower core count processors in the E7-48xx v2 product family, at least from a pure processor performance perspective.
Intel also has refreshed the E7-88xx v2 product family that is meant for eight-socket and larger servers. For some reason (probably for HPC use), Intel does have “frequency-optimized”, lower core-count models in this product family, as you can see in Table 2.
| Processor | Physical Cores | L3 Cache | Base Clock | Turbo Clock | Price |
| E7-8890 v2 | 15 | 37.5 MB | 2.8GHz | 3.4GHz | $6,841.00 |
| E7-8857 v2 | 12 | 30 MB | 3.0GHz | 3.6GHz | $3,838.00 |
| E7-8891 v2 | 10 | 37.5 MB | 3.2GHz | 3.7GHz | $6,841.00 |
| E7-8893 v2 | 6 | 37.5 MB | 3.4GHz | 3.7GHz | $6,841.00 |
Table 2: Selected Intel E7-88xx v2 Processors
I could see some scenarios where you might want to get an eight-socket server with the six-core E7-8893 v2, so that you could have the same physical core count, while having double the memory capacity and much better single-threaded processor performance than a four-socket server with the twelve-core E7-4860 v2. The hardware cost would be significantly higher, since you would be buying eight processors for $6,841.00 each instead of four processors at $3,838.00 each, but for many organizations, that would not be a major issue.
Some server vendors may offer the Xeon E7-88xx v2 processors in their four-socket server models, since they are pin-compatible, which would give us a lot more flexibility as far as processor selection goes. I really wish Intel had “frequency-optimized” models in their Xeon E7-48xx v2 product family, to make this even easier.
