IBM System p (IBM POWER) hardware supports Logical Partitioning (LPAR), and more specifically Dynamic Logical Partitioning, giving the capability to the logical partition to be reconfigured dynamically, without shutting down.
It enables memory, CPU capacity and I/O interfaces to be moved between LPARs.
IBM introduced LPARs on POWER4-based server as a mainframe-inspired technology. It is supported on AIX, i5/OS and Linux (running on POWER architecture), although on Linux changes are limited to CPU capacity and I/O devices.
AIX running on IBM pSeries (now known as System p) first introduced support for Dynamic Logical Partitions in version 5.2. These partitions could run AIX 5.1, 5.2 or Linux.
Later, the POWER5 processor added more capabilities, including micro-partitioning: up to ten LPARs could be configured per processor, with a single multiprocessor server supporting a theoretical maximum of 254 LPARs (and thus up to 254 independent operating systems).