CPU Reserve

A parent partition can supply the CPU reserve for each child partition. The hypervisor guarantees that this fraction of CPU time is available to each virtual processor within the partition. The CPU reserve setting does not necessarily mean that each virtual processor will consume the entire reserve. If a virtual processor is idle, other virtual processors can consume the available processor cycles.

The CPU reserve is specified as a fraction of a logical processor's capacity. A reserve value of 0.5 indicates that 50% of a logical processor is reserved for each virtual processor in the partition. Valid reserve values range from 0 (no reserve) to 1 (in which case each virtual processor is guaranteed to get 100% of a logical processor if required). The reserve value cannot be greater than the CPU Cap.

The reserve value is expressed as an integer ranging from 0x00000000 to 0x00010000. For example, the value 0x0000C000 indicates 0.75, or 75% of a logical processor.

The total reserves for all virtual processors cannot exceed the number of logical processors in the system. Reserves are not guaranteed if the number of virtual processors in a partition exceeds the number of logical processors that are available for scheduling. If the number of virtual processors in a partition is set to greater than the number of logical processors, the hypervisor might reset the partition's reserve to zero.

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Build date: 11/16/2013