Live Partition Mobility – Enterprise solutions

3.1.4 Live Partition Mobility

LPM allows you to move a running LPAR from one system to another without disruption. Inactive partition mobility allows you to move a powered-off LPAR from one system to another one.

LPM provides systems management flexibility and improves system availability by avoiding the following situations:

Ê Planned outages for hardware upgrade or firmware maintenance.

Ê Unplanned downtime. With preventive failure management, if a server indicates a potential failure, you can move its LPARs to another server before the failure occurs.

For more information and requirements for LPM, see IBM PowerVM Live Partition Mobility, SG24-7460.

HMCV10R1 and VIOS 3.1.3 or later provide the following enhancements to the Live Partition Mobility Feature:

Ê Automatically choose fastest network for LPM memory transfer

Ê Allow LPM when a virtual optical device is assigned to a partition

3.1.5 Active Memory Expansion

Active Memory Expansion (AME) is an optional feature code (#EM8F) that belongs to the technologies under the PowerVM umbrella and enables memory expansion on the system.

AME is an innovative technology that supports the AIX operating system. It helps enable the effective maximum memory capacity to be larger than the true physical memory maximum. Compression and decompression of memory content can enable memory expansion up to 100% or more. This expansion can enable a partition to complete significantly more work or support more users with the same physical amount of memory. Similarly, it can enable a server to run more partitions and do more work for the same physical amount of memory.

142  IBM Power E1080: Technical Overview and Introduction

AME uses CPU resources to compress and decompress the memory contents. The trade-off of memory capacity for processor cycles can be an excellent choice, but the degree of expansion varies about how compressible the memory content is. It also depends on having adequate spare CPU capacity available for this compression and decompression.

The Power E1080 includes a hardware accelerator that is designed to boost AME efficiency and uses less processor core resources. Each AIX partition can turn on or turn off AME. Control parameters set the amount of expansion that is wanted in each partition to help control the amount of CPU used by the AME function.

An IPL is required for the specific partition that is turning memory expansion. When enabled,

monitoring capabilities are available in standard AIX performance tools, such as lparstat,

vmstat, topas, and svmon.

A planning tool is included with AIX, which enables you to sample workloads and estimate how expandable the partition’s memory is and much CPU resource is needed. The feature can be ordered with the initial order of the Power E1080 or as an MES order. A software key is provided when the enablement feature is ordered, which is applied to the system node. An IPL is not required to enable the system node. The key is specific to an individual system and is permanent. It cannot be moved to a different server.

Note: IBM i does not support AME.