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.

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.
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.
COD Preference:
COD (Cluster-On-Die) splits the cores/caches into two halves. This improves performance for some applications. Setting the COD preference to Enable does not guarantee that COD will always be enabled. COD is only enabled if the current hardware configuration allows it. Note, COD takes precedence over early snoop.