IBM Power 780, Technical Overview And Introduction

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Chapter 3. Virtualization
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To help you do this study, a planning tool is included with AIX 6.1 Technology Level 4, allowing
you to sample actual workloads and estimate how expandable the partition's memory is and
how much CPU resource is needed. Any model Power System can run the planning tool.
Figure 3-4 shows an example of the output that is returned by this planning tool. The tool
outputs various real memory and CPU resource combinations to achieve the desired effective
memory. It also recommends one particular combination. In this example, the tool
recommends that you allocate 13% of processing power (2.13 physical processors in this
setup) to benefit from 119% extra memory capacity.
Figure 3-4 Output from Active Memory Expansion planning tool
Active Memory Expansion Modeled Statistics:
-------------------------------------------
Modeled Expanded Memory Size : 52.00 GB
Achievable Compression ratio :4.51
Expansion Modeled True Modeled CPU Usage
Factor Memory Size Memory Gain Estimate
--------- ------------- ------------------ -----------
1.40 37.25 GB 14.75 GB [ 40%] 0.00 [ 0%]
1.80 29.00 GB 23.00 GB [ 79%] 0.87 [ 5%]
2.19 23.75 GB 28.25 GB [119%] 2.13 [ 13%]
2.57 20.25 GB 31.75 GB [157%] 2.96 [ 18%]
2.98 17.50 GB 34.50 GB [197%] 3.61 [ 23%]
3.36 15.50 GB 36.50 GB [235%] 4.09 [ 26%]
Active Memory Expansion Recommendation:
---------------------------------------
The recommended AME configuration for this workload is to configure the LPAR
with a memory size of 23.75 GB and to configure a memory expansion factor
of 2.19. This will result in a memory gain of 119%. With this
configuration, the estimated CPU usage due to AME is approximately 2.13
physical processors, and the estimated overall peak CPU resource required for
the LPAR is 11.65 physical processors.