SPEC CPU2006 Platform Settings for IBM Systems

Operating System Tuning Parameters

Zone Reclaim:
Zone reclaim allows the reclaiming of pages from a zone if the number of free pages falls below a watermark even if other zones still have enough pages available. Reclaiming a page can be more beneficial than taking the performance penalties that are associated with allocating a page on a remote zone, especially for NUMA machines.
Disabling Intel Idle Driver:
intel_idle is a Linux cpuidle driver that loads on specific Intel processors replacing the legacy ACPI processor_idle driver. The intel_idle driver uses its built-in logic to control the processor C-state directly, bypassing the BIOS/UEFI settings. The intel_idle driver can be disabled by adding "intel_idle.max_cstate=0" Linux kernel parameter. This will make the BIOS/UEFI C-state settings effective again.

Firmware / BIOS / Microcode Settings

Operating Mode Selections: (Default="Efficiency -Favor Performance")
The average customer doesn't know the best way to set each individual power/performance feature for their specific environment. Because of this, a menu option is provided that can help a customer optimize the system for things such as minimum power usage/acoustic levels, maximum efficiency, Energy Star optimization, or maximum performance.
Power C-States:
Enabling the CPU States causes the CPU to enter a low-power mode when the CPU is idle.
Turbo Mode:
Enabling turbo mode can boost the overall CPU performance when all CPU cores are not being fully utilized.
Turbo Boost:
This BIOS option can be set to Power Optimized or Traditional. When Power Optimized is selected, Intel Turbo Boost Technology engages after Performance state P0 is sustained for longer than two seconds. When Traditional is selected, Intel Turbo Boost Technology is engaged even for P0 requests less than two seconds.
Hyper-Threading:
Enabling Hyper-Threading allows each physical CPU core to have two logical cores. With Hyper-Threading enable, the software can schedule concurrent execution threads to the logical cores and hopefully improve the utilization of the resources inside the physical CPU cores.