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Cloud instance rightsizing

Before moving a virtual machine to Google Cloud, you need to determine which instance types and sizes to use. Velostrata has a rightsizing feature to help you answer this question. The feature includes built-in usage monitoring and recommends instance types optimized for cost and performance.

Rightsizing provides two types of recommendations:

  1. Performance-based recommendations: Recommends Google Cloud instances based on the CPU and RAM currently allocated to the on-premises VM. This recommendation is the default.
  2. Cost-based recommendations: Recommends Google Cloud instances based on:
    • The current CPU and RAM configuration of the on-premises VM.
    • The average usage of this VM during a given period. To use this option, you must activate rightsizing monitoring with vSphere for this group of VMs and allow time for Velostrata to analyze usage.

Recommendations are accessible from the vCenter Web Client user interface, PowerShell module, REST API, and Velostrata Waves for mass migration planning.

Suggested options also include expected monthly costs. These are relative cost estimates and not intended for billing forecasts. The cost estimate uses on-demand compute prices with sustained-use discounts only; it doesn't include disk and network cost or consider reduced-cost options.

Rightsizing VMs from vSphere

When you specify which VMs to monitor, the on-premises Velostrata On-Premises Backend virtual appliance starts collecting and analyzing utilization statistics from VMware vSphere. It classifies the activity it observes into patterns based on estimated memory and CPU needs.

For better recommendations, Velostrata recommends monitoring the migrated workloads for at least seven consecutive days (or one typical business week). Velostrata warns you when the monitoring period is insufficient for an adequate recommendation.

Even if the monitoring period is insufficient, Velostrata still offers a cost-optimized recommendation based on the data available.

Rightsizing VMs from AWS

Velostrata also offers rightsizing recommendations for VMs currently hosted on AWS. Unlike rightsizing recommendations for vSphere, recommendations for AWS instances are not based on monitoring of instance usage; they are based upon the CPU and memory configuration of the source instance.

Next steps

For more information about using the rightsizing feature, see Rightsizing instances in a wave or Running or migrating VMs.