26 IBM System x3850 X6 and x3950 X6 Planning and Implementation GuideTurbo Boost Technology 2.0The Intel Xeon E7-8800/4800 v2 processor family brings enhanced capabilities of changingprocessor speed with new generation of Intel Turbo Boost 2.0 technology.Intel Turbo Boost Technology dynamically saves power on unused processor cores andincreases the clock speed of the cores in use. Depending on current workload, Intel TurboBoost Technology allows a dynamic increase in the clock speed of the active cores to gain aperformance boost. For example, a 3.4GHz 15-core processor can overclock the cores up to3.7 GHz.Turbo Boost Technology is available on a per-processor basis for the X6 systems. ForACPI-aware operating systems and hypervisors such as Microsoft Windows 2008/2012,RHEL 5/6, SLES 11, VMware ESXi 4.1, and later, no changes are required to take advantageof it. Turbo Boost Technology can be engaged with any number of cores enabled and active,resulting in increased performance of both multi-threaded and single-threaded workloads.Turbo Boost Technology dynamically saves power on unused processor cores and increasesthe clock speed of the cores in use. In addition, it can temporarily increase speed of all coresby intelligently managing power and thermal headroom. For example, a 2.5 GHz 15-coreprocessor (E7-8880 v2) can temporarily run all 15 active cores at 2.9 GHz. With only twocores active, the same processor can run those active cores at 3.0 GHz. When the cores areneeded again, they are turned back on dynamically and the processor frequency is adjustedaccordingly.When temperature, power, or current exceeds factory-configured limits and the processor isrunning above the base operating frequency, the processor automatically steps the corefrequency back down to reduce temperature, power, and current. The processor thenmonitors temperature, power, and current, and re-evaluates. At any given time, all activecores run at the same frequency.For more information about Turbo Boost Technology, go to the following website:http://www.intel.com/technology/turboboost/QuickPath InterconnectThe Intel Xeon E7 processors implemented in IBM X6 servers include two integrated memorycontrollers in each processor. Processor-to-processor communication is carried overshared-clock or coherent quick path interconnect (QPI) links. Each processor has three QPIlinks to connect to other processors.Figure 2-19 shows the QPI configurations. On the left is how the four sockets of the x3850 X6are connected together. On the right is how all eight sockets of the x3950 X6 are connectedtogether.Figure 2-19 QPI links between processors4 3217 8564 321x3950 X6 - 8 socketsx3850 X64 sockets
