Cloud Instance Rightsizing Overview

 When moving a virtual machine to the cloud, the question of instance rightsizing comes up - out of the many different instance types and sizes offered, which should you chose? Velostrata has developed a rightsizing feature to help answer this question. The feature includes built-in usage monitoring and a recommendation engine that provides cost- and performance-optimized cloud instance type and size recommendations.

Based on the user indicating which of the virtual machines to watch, the Velostrata virtual appliance on-premises starts collecting and analyzing utilization statistics, at a fine resolution, from VMware vSphere. The observed activity patterns are then classified into utilization buckets, based on which memory and CPU needs are estimated.

For better recommendation accuracy, Velostrata recommends at least 7 active days as a watch period, or a typical business cycle for the monitored workloads. A warning is shown when the activity period recorded is insufficient in order to provide a recommendation with an adequate confidence level. Nevertheless, a cost-optimized recommendation is still offered based on the available observation.

Cost-optimized recommendations are based on the observed utilization and activity classification. Performance-optimized recommendations are based on the provisioned VM's characteristics. Such recommendations are available in the Run In Cloud, Test Clone, Migrate and Offline Migration operations, and are accessible in the vCenter Web Client user interface, PowerShell module, REST API, and Automation Runbook Tool for mass migration planning.

For each operation where recommendations are presented, the virtual machine’s provisioned vCPUs, RAM and number of disks are indicated, as well as the observed CPU and RAM usage classification. Recommendations include three options performance-optimized cloud instance options, as well as three cost-optimized options. The cumulative monitoring and active durations are indicated in days. In the vCenter Web Client wizards, the lowest cost performance-optimized option is selected by default. Clicking any other option sets the target instance selection accordingly. Only relevant options are presented, based on the number of disks, storage type and supported types by region as applicable to the target cloud in which the previously selected Velostrata CloudExtension resides.

Presented options also include expected monthly costs. These are to be used as relative cost indicators and not used for actual billing forecasting purposes. The expected cost uses on-demand compute price lists only, and does not include disk and network costs, and does not consider reduced cost options such as discount agreements, pre-purchased compute and reserved instances, spot and pre-emptive instances, or other price reduction plans. If the online price list is not accessible (internet access required), no cost-optimized recommendations are provided.