SPEC CPU2006 Platform Settings for Intel-based systems
- Hardware Prefetch:
-
This BIOS option allows the enabling/disabling of a processor mechanism
to prefetch data into the cache according to a pattern-recognition algorithm
In some cases, setting this option to Disabled may improve performance.
Users should only disable this option after performing application benchmarking
to verify improved performance in their environment.
- Adjacent Sector Prefetch:
-
This BIOS option allows the enabling/disabling of a processor mechanism
to fetch the adjacent cache line within a 128-byte sector that contains the
data needed due to a cache line miss.
In some cases, setting this option to Disabled may improve performance.
Users should only disable this option after performing application benchmarking
to verify improved performance in their environment.
- High Bandwidth:
- Enabling this option allows the chipset to defer memory transactions and
process them out of order for optimal performance.
- Patrol Scrub:
-
Sets the patrol scrubbing which proactively searches the memory to repair
correctable errors.
- Per Core P-State:
-
When per-core P-states are enabled, each physical CPU core can operate
at separate frequencies. If disabled, all cores in a package will operate
at the highest resolved frequency of all active threads.
If minimum variablility is desired, disable per core P-states.
- 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.
- C-States:
-
Enabling C-states allows the OS to place the CPUs into lower power states when idle.
The ACPI C-state limit menu can be used to restrict the available C-states.
- C1 Enhanced Mode:
-
Enabling C1E (C1 enhanced) state can save power by halting CPU cores that are idle.
- Active Energy Manager:
-
Select this choice to enable or disable AEM Power Capping.
When Power Capping is enabled, AEM applicaton can limit the maximum power consumed by this system.
- Platform Controlled Type:
-
Maximum Performance allows the most aggressive use of turbo and power management functions are disabled, thereby increasing power consumption.
- Memory Power Management:
-
Disable provides maximum performance but minimum power savings.
Automatic is suitable for most applications.
- Energy Efficient Turbo:
-
When energy efficient turbo is enabled, the CPU's optimal turbo frequency will be turned dynamically based on CPU utilization.
The power/performnce bias setting also influences energy efficient turbo.
- Processor Performance States:
-
Enabling processor performance states saves power by reducing speed and voltage as the CPU utilized is reduced.
- Uncore Frequency Scaling:
-
When enabled, the CPU uncore will dynamically change speed based on the wirkload.
All miscellaneous logic inside the CPU package is considered the uncore.
- Early Snoop Preference:
-
Early snoop may increase performance for some workloads.
Setting the early snoop performance to Enable does not gurantee that early snoop will always be enabled.
Early snoop only enabled if the current hardware configuration allows it and COD is disabled.
Note that COD mode takes precedence over early snoop.
- Power/Performance Bias:
-
Power/Performance Bias determines how aggressively the CPU will be power managed and placed into turbo.