Data source requirements for VM resizing

• An Instrumented VM is required for Balanced and Conservative optimization behaviors.
• Use the Instrumented VM or the specific data source for your cloud provider to collect the memory and storage utilization metrics. For example, for AWS, you can choose to instrument the VM or run the AWS monitoring script to collect the metrics.
  
  If you do not use any of these data sources, memory and storage utilization metrics will not be collected and hence, will be reported as N/A on the user interface. As a result, the migration simulation results will be based on the Lift-and-Shift strategy, and the Overallocated VM recommendation will be based on CPU usage only.

When a VM is instrumented, the memory utilization value is based on the real memory of the VM. If you do not use an Instrumented VM, the memory utilization metric value is based on the data collected by the Hypervisor, and might be over-reported. As a result, the migration simulation results might propose an instance type with a larger configuration than required. Also, some VMs might not be detected as overallocated.

If you do not use an Instrumented VM, the memory and storage utilization values will not be collected. As a result:

• The memory and storage utilization values will be reported as N/A on the user interface.
• The Overallocated VM recommendation will be based on CPU usage only.
• Because the memory utilization value is not available, simulation will use the configured memory to propose the target VM.
• For simulation that is based on the Aggressive optimization behavior, the Configured storage and Used storage values will not be available. Hence, the cost reported in the simulation results will not include the cost of storage.