Solutions > Plan and forecast the capacity requirements of the virtual environment > Calculate the number of VMs you can add to the virtual infrastructure

Calculate the number of VMs you can add to the virtual infrastructure

Based on the current host resources, you can analyze how many more virtual machines you can add to your virtual infrastructure. To perform this analysis, define a resource container with the hosts where you want to add VMs, and define a usage profile that contains VMs that represent the new VMs you want to add.

  1. Click Capacity Planning > Capacity Planner.
  2. Load a resource container.
    The resources within the container are considered during the analysis. The calculation checks the availability of these resources on hosts within the resource container:
    • CPU utilization
    • Memory utilization
    • Disk space consumption and disk IOPs
    • Network consumption
  3. Load a usage profile that contains VMs that represent the VMs you want to add.
    The calculations checks these consumption metrics on the VMs:
    • CPU
    • Memory
    • Disk space
  4. Click Calculate.

Depending on the size of the resource container and usage profile, the calculation can take a few minutes.

The Capacity Planning Results table contains the number of VMs you can add to the hosts within the resource container. The resource which prevents more VMs from being added is displayed next to the number of VMs. The table displays this information for each cluster:

  • Workload (constraint)
    If you specified the number of VMs you want to add and their specifications in the Workload section, this column displays how many times you can add all of them. For information about workload settings, see Customize capacity planning calculations.
  • Small VMs
    The number of VMs you can add if you only add the smallest VMs within the usage profile, which consume the least resources.
  • Average VMs
    The number of VMs you can add, based on the average resources consumed by VMs within the usage profile.
  • Large VMs
    The number of VMs you can add if you only add the largest VMs within the usage profile, which consume the most resources.

Display the capacity plan in charts

After calculating a capacity plan, click Capacity to display a visual representation of the number of VMs you can add.

The bar chart shows all the clusters or hosts. The consumed resources are represented per cluster or host. The chart provides an overview of the latest resource utilization information in the resource container.

The Remaining Capacity bars of the bar charts on the right show the number of VMs you can add.

The charts take into account the settings you specify in Advanced Options and are refreshed when you click Update in the Advanced Options section, or click Calculate in the capacity planning module. For more information, see Customize capacity planning calculations.

Calculate VM sizes

Virtualization Manager calculates the sizes of small, average, and large VMs based on the information in the usage profile.

If the usage profile does not include clusters, the sizes are calculated based on all the averaged values per resource included in the usage profile. You can view these values in the Details view of the usage profile.

  • Small
    The minimum value of all the averaged values of the resources.
  • Average
    The average of all the averaged values of the resources.
  • Large
    The maximum value of all the averaged values of the resources.

If the Usage Profile contains clusters, the calculation uses minimum, maximum, and average values from cluster trends.