Technical data

White Paper ⏐Performance Report PRIMERGY TX150 S6 Version: 5.1, November 2008

The Xeon processor comparison diagram shows measurements with four different Xeon CPUs measured with the

PRIMERGY TX150 S6. All other configuration details remained unchanged during the measurements.

Obviously the throughput changes when using different CPUs with different frequencies or different number of cores per

chip. That is exactly what the bars show in the diagram above. The measurement with the most powerful Xeon X3370

(quad-core 3.0 GHz) CPU delivers the highest throughput and the measurement with the Xeon E3120 (dual-core 3.16

GHz) CPU which has nearly the same frequency but half the number of cores per chip delivers the lowest throughput in

ssj_ops (left y-axis). It is also visible that the ratio of the performance gain and the performance loss respectively with the

different CPUs is nearly the same at each target load level (x-axis). But looking at the average power consumption

curves (right y-axis) the behavior varies for the different load levels.

The ratio of power consumption between the different CPUs changes with every additional 10% of the target load. During

active idle the difference is very small. That relates to the power management features of the CPUs and the operating

system. They enable the CPUs to scale down the frequency and core voltage to a level where the CPUs consume the

lowest power provided that the CPUs are idle. So the power consumption for the different CPUs is almost the same at

active idle. As you can see this is not true for the Xeon X3220 processor. This is due to the fact that this processor is

based on another manufacturing technology, 65 nm compared to 45 nm on all other processors. The 45 nm manufac-

turing technology enables the processors to consume less power and brings additional power management features. At

the higher load levels the influence of the power management features is only marginal. This is exactly where the Xeon

X3360 processor can play to its strength. Although it has the same TDP of 95 watts as the Xeon X3220 and X3370 the

Xeon X3360 processor consumes much lower power at higher load levels. This is related to the lower frequency com-

pared to the Xeon X3370 processor and to the less power consuming manufacturing technology of 45 nm compared to

65 nm in the case of the Xeon X3230 processor. At 100% load the power consumption difference to the Xeon X3370

processor is 23 watts.

When looking at the Xeon E3120 processor you can see that it consumes the lowest power of all processors. But the

lower power consumption of this CPU can not compensate the enormous performance drawback which is caused by the

fact that this CPU has only 2 cores per chip. The Xeon X3360 processor shows the ideal balance between performance

and power consumption and thus makes it the best choice for SPECpower_ssj2008.

The following diagram displays a comparison of additional configuration options. It only shows the differences in power

consumption for each load level but no performance changes. The performance depends on the choice of the CPU as

you could see in the diagram before. All the additional configuration changes we made in the following comparison, like

adding more memory, more hard disks, other and additional

Power Supply Units (PSUs) and turning off power manage-

ment features, do not have any or only very limited influence on performance.