Active Memory Sharing - IBM Power Systems E870 Technical Overview And Introduction

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Server Evacuation: This PowerVM function allows you to perform a server evacuation
operation. Server Evacuation is used to move all migration-capable LPARs from one
system to another if there are no active migrations in progress on the source or the target
servers
With Server evacuation feature, multiple migrations can occur based on the concurrency
setting of the HMC. Migrations are performed as sets, with the next set of migrations starting
when the previous set completes. Any upgrade or maintenance operations can be performed
after all the partitions are migrated and the source system is powered off.
You can migrate all the migration-capable AIX, IBM i and Linux partitions from the source
server to the destination server by running the following command from the HMC command
line:
migrlpar -o m -m source_server -t target_server --all
Hardware and operating system requirements for Live Partition Mobility
Live Partition Mobility is supported by default with enterprise systems, and it is supported in
compliance with all operating systems that are compatible with POWER8 technology.
The VIOS partition itself cannot be migrated.
For more information about Live Partition Mobility and how to implement it, see IBM PowerVM
Live Partition Mobility (Obsolete - See Abstract for Information), SG24-7460.

3.4.6 Active Memory Sharing

Active Memory Sharing is an IBM PowerVM advanced memory virtualization technology that
provides system memory virtualization capabilities to IBM Power Systems, allowing multiple
partitions to share a common pool of physical memory.
Active Memory Sharing is available only with the Enterprise version of PowerVM.
The physical memory of an IBM Power System can be assigned to multiple partitions in either
dedicated or shared mode. The system administrator can assign some physical memory to a
partition and some physical memory to a pool that is shared by other partitions. A single
partition can have either dedicated or shared memory:
With a pure dedicated memory model, the system administrator's task is to optimize
available memory distribution among partitions. When a partition suffers degradation
because of memory constraints and other partitions have unused memory, the
administrator can manually issue a dynamic memory reconfiguration.
With a shared memory model, the system automatically decides the optimal distribution of
the physical memory to partitions and adjusts the memory assignment based on partition
load. The administrator reserves physical memory for the shared memory pool, assigns
partitions to the pool, and provides access limits to the pool.
Active Memory Sharing can be used to increase memory usage on the system either by
decreasing the global memory requirement or by allowing the creation of additional partitions
on an existing system. Active Memory Sharing can be used in parallel with Active Memory
Expansion on a system running a mixed workload of several operating systems. For example,
AIX partitions can take advantage of Active Memory Expansion. Other operating systems
take advantage of Active Memory Sharing also.
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IBM Power Systems E870 and E880 Technical Overview and Introduction
Draft Document for Review October 14, 2014 10:19 am