The microphone-partitioning is a logical form of Partitionnement introduces by IBM on the systems using the processors POWER5 (typically the operating system AIX).

Microphone-Partitioning works with a file of divided processors which divides the physical processors rather than to have a dedicated attribution. This file of divided processors can support up to ten times more images OS than with physical processors (one can thus make ten partitions with a physical CPU).

There is no bond between the physical microphone-partitions and processors: it is the layer Hyperviseur which allocates the resources according to the rules defined during the creation of the partitions. This chouche Hyperviseur is a function of the Firmware and is found in the waiters POWER5 and POWER6, which one uses microphone-partitioning or not. It is thus possible to allocate fractions of processor to a partition (for example 1.5 CPU for a partition, and 2.5 for another on a machine having 4 processors). It is possible to dynamically change this distribution between the microphone-partitions (much more easily than the distribution memory).