Demystifying Hardware - SQL Server 2012 Internals and Troubleshooting - page 39

Classic Intel Processor Numbering
In order to understand older Intel processor numbers, you need to know how to decode “classic” Intel
processor numbers. By classic we mean Intel Xeon processors produced from about 2006 until April
2011 (when Intel introduced a new processor numbering
system for new and upcoming processors).

Processor Name

Knowing how to decode the processor model number
is a very handy skill to have when you want to under-
stand the capabilities, relative age, and relative per-
formance of a particular processor. An example of an
Intel processor number is shown in Figure 2-1.

Intel® Xeon® processor X5482

Brand Number

FIGURE 2-1

Intel Xeon processor numbers are categorized in four-
digit numerical sequences, plus an alpha prei x that indicates whether it is optimized for electrical
power usage or performance. The alpha prei xes are as follows:

➤

X, meaning performance

➤

E, meaning mainstream

➤

L, meaning power optimized

The model number starts with 3, 5, or 7, depending on the server form factor for which the proces-
sor is designed. If the processor number starts with a 3, it is designed for a single-socket server; if
it starts with a 5, it is designed for a two-socket server; and if it starts with a 7, it is designed for
a four-socket or more server. The second digit of the model number designates the generation, or
relative age, of a processor. For example, the Xeon 5100 series was launched in Q2 2006, while the
Xeon 5300 series was launched in Q4 2006, and the Xeon 5400 series was launched in Q4 2007.

For a more complete example, a Xeon X7560 is a high-end performance processor for multi-
processor systems, an Intel Xeon E5540 is a mainstream processor for dual-processor systems,
while an Intel Xeon L5530 is a power-optimized processor for dual-processor systems. The i nal
three digits denote the generation and performance of the processor; for example, a Xeon X7560
processor would be newer and probably more capable than a Xeon X7460 processor. Higher
numbers for the last three digits of the model number mean a newer generation in the
family — for example, 560 is a newer generation than 460.

You should always choose the performance models, with the X model prei x, for SQL Server usage.
The additional cost of an X series Xeon processor, compared to an E series, is minimal compared
to the overall hardware and SQL Server license cost of a database server system. You should also
avoid the power-optimized L series, as these can reduce processor performance by 20% to 30%
while only saving 20 to 30 watts of power per processor, which is pretty insignii cant compared to
the overall electrical power usage of a typical database server (with its cooling fans, internal drives,
power supplies, etc.). Of course, it would be a different story if you needed dozens or hundreds of
web servers instead of a small number of mission-critical database servers, as the overall power
savings would be pretty signii cant in that case.