A colleague of mine contacted me during the week to ask how one could determine if a POWER7 system was capable of Active Memory Expansion. I thought I'd share my response with everyone who follows my blog.

You can check if the system is capable of providing Active Memory Expansion (AME), from the HMC command line using the lssyscfg command, as shown here:

hscroot@hmc1:~> lssyscfg -r sys -m Server-8233-E8B-SN1000 -F active_mem_expansion_capable

Alternatively you can view the capabilities of the managed system from the HMC GUI, under System properties/Capabilities, as shown in the following image.


Once youve concluded that your POWER7 system is AME capable, the next step is to check if AME is enabled or disabled for an LPAR. This is easily done from the AIX command line with the lparstat and/or amepat commands, as shown in the following example:

;Running lparstat and amepat on a LPAR with AME disabled.

$ lparstat -i| grep Exp
Target Memory Expansion Factor : -
Target Memory Expansion Size : -

$ amepat | grep Expan
WARNING: Running in no modeling mode.
Active Memory Expansion : Disabled

;Running lparstat and amepat on a LPAR with AME enabled.

$ lparstat -i | grep -i exp

Memory Mode : Dedicated-Expanded

Target Memory Expansion Factor : 1.00

Target Memory Expansion Size : 6144 MB

$ amepat | grep -i exp

WARNING: Running in no modeling mode.

Active Memory Expansion : Enabled

Target Expanded Memory Size : 6.00 GB

Target Memory Expansion factor : 1.00

Note that I deliberately ran these commands as a non-root user to highlight the fact that you dont need root access to ascertain whether or not AME is active on an LPAR.

By the way, did you know that AME is now supported in SAP production environments running on AIX and POWER7? Both SAP application servers, as well as database servers running DB2 LUW are supported. Unfortunately theres no support for LPARs with Oracle RDBMS at this stage. Thanks to George Manousos from IBM Australia for providing me with this update.

Please refer to the following SAP note.


The SAP note also states:

Specific tests have been successfully executed with SAP ERP 6.0 (ABAP)

workload. The results of those test can be found in the following whitepaper:



As AME is not recommended with large page support, AME will disable AIX

64KB pages by default.

AME monitoring capability in CCMS

Monitoring capabilities are available with saposcol v12.46 for more details see SAP note 710975.

It looks as though SAP have been quick to support AME on AIX/POWER7. This is a great benefit to SAP customers running with PowerVM on the IBM POWER platform. The following screenshot shows the SAP CCMS with AME statistics being reported.

PowerVM Integration into SAP CCMS Monitoring expanded to include Virtualized Memory Metrics

The SAP AIX porting team continues in further improving the integration of PowerVM into SAP system monitoring. While in the past already most processor and AIX virtualization metrics could be monitored via CCMS, now POWER7 Active Memory Expansion (AME) has been included. Customers will find a new memory section in the respective CCMS-panel as depicted in this screen shot.


For those who are not familiar with what AME actually is and how it can benefit you, I suggest you take a look at the IBM AME Wiki site first:


And watch Nigel Griffiths AME movie: