Quoting from the IBM official announcement:
In a showcase technology forum here today, IBM highlighted a breakthrough virtualization technique behind IBM’s POWER6 microprocessor with a demonstration of Live Partition Mobility, a feature that will enable the movement of computer workloads from one IBM UNIX system to another while both systems are running.
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Live Partition Mobility, currently in beta testing with general availability planned later this year, is a continuous availability feature that will enable POWER6-based servers, such as the System p 570, to move live logical partitions — including the entire operating system and all its running applications — from one server to another while the systems are running.
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Because Live Partition Mobility is implemented in the POWER6 chip, hardware and its associated firmware, the feature is operating system independent, allowing the movement of AIX or Linux operating systems and associated running workloads. For instance, using Live Partition Mobility customers will be able to dynamically consolidate UNIX or Linux workloads — without interruption — onto fewer servers during off-peak times, allowing them to turn off computers and save energy.
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Live Partition Mobility works by replicating memory pages from one partition to another in a way that is transparent to the operating system and applications running in the partition. It can thus be used to migrate workloads running on AIX or Linux operating systems on any POWER6 partition and includes support for AIX 5.2, AIX 5.3, AIX 6 and for both Red Hat and Novell SUSE Linux.
The virtualization process begins with a warm-up period during which the bulk of the memory is replicated between the source server and destination partitions. A guest operating system can then be migrated from one host to another in less than two seconds without losing transactions, even when running applications with high utilization of CPU and I/O resources, such as a large database several hundreds of gigabytes in size processing thousands of transactions per minute…