You define scenarios that can potentially add workloads to actual data centers. vRealize Operations Manager models the scenario and calculates whether your desired workload can fit in the targeted data center or custom data center. You can also define scenarios that can potentially remove workloads from data centers. vRealize Operations Manager calculates the time remaining and capacity remaining on the cluster when workloads are removed from the cluster.

Where You Find What-If Analysis - Workload

From the Home screen, select What-If Analysis under Optimize Capacity in the left pane. From the What-If Analysis screen, click Add VMs or Remove VMs in the pane titled Workload Planning.

How What-If Analysis - Add Workload Works

This feature of Capacity Optimization enables you to forecast successfully the impact of adding a workload to an application. By trying various scenarios, you can arrive at an optimum configuration. Once you select the Workload Planning screen, you can choose the exact data center or custom data center where you want to locate the new workload. You can even pick a specific cluster where the workload is to reside.

In choosing the profile of your workload, you have two options:

  • Configure the workload manually by specifying vCPUs, memory, storage, and expected use percentage. You have the further option to click Advanced Configuration and specify more precise characteristics for your workload.

  • Use an existing VM or VMs as templates, importing all the attributes of the selected VMs to your workload scenario. The system allows you to specify how many copies of each selected VM you want to add to the proposed workload.

When you have set the profile for the new workload, enter the start and end date for the period when you want the workload to be active. The default is: starting today and ending one year from today. The system can project scenarios ending up to one year from the current date.

At this point, you can save the scenario to edit or run later on. A list of saved scenarios is available on the What-If Analysis main page. Otherwise, run the scenario to get the vRealize Operations Manager analysis and assessment of your plan.

The system lets you know immediately if the proposed workload fits or does not fit in the suggested location. If it fits, the results list the prime target cluster and any additional possible locations. The system also projects time remaining before the workload runs out of resources. If you select scenario details, the system displays a graphic depiction of resource use. For each attribute value - vCPU, memory, and storage - the amount by which the workload increases the percentage of total application capacity used is shown against a time line. The graph shows the existing percentage used in blue and the total of existing usage and added usage as a percentage of total capacity in green.

If the proposed workload does not fit, the system announces the outcome and provides the following information:

  • How much the added workload reduces the time remaining for the target cluster, for example, from one year to zero.

  • The discrepancy between the space available in the target cluster and what the proposed workload requires, for example, 100 GB of memory.

  • The cost of the workload on the VMware Hybrid Cloud and on the public cloud.

About Clouds

When you run a scenario in What-If Analysis, you get a recommendation based on cost relative to workload placement on different clouds. This cost-based recommendation varies for different clouds.

Private Cloud and VMware Cloud on AWS costs are computed based on resource usage levels.

Public clouds, AWS, IBM Cloud, Google Cloud, Microsoft Azure and user-defined cloud costs are dependent on the selected configuration, that is, for the allocated resources. These public cloud instances are selected based on the close proximity rule, with simulated resource allocation values and in some scenarios, the exact configuration match available in the cloud instance list is not available. Due to this issue, these public cloud costs can be inherently higher in comparison.

How What-If Analysis - Remove Workload Works

This feature of Capacity Optimization enables you to forecast successfully the impact of removing a workload. By trying various scenarios, you can arrive at an optimum configuration. Once you select the Workload Planning screen, you can choose VMs from the concrete cluster data center or from the customer data center from which you want to remove the existing workload.

While removing workloads, you have two options to define the workload:

  • Select existing VMs and use their projected utilization to evaluate the impact of removing workloads.

  • Configure the workload manually by specifying the vCPUs, memory, storage, and expected use percentage.

Enter the start and end date for the period during which you want the workload to be removed. By default, the start date is today and the end date is one year from today. The end date is left empty by default. The system can project scenarios ending up to one year from the current date.

At this point, you can save the scenario to edit or run later on. A list of saved scenarios is available on the What-If Analysis main page. Otherwise, run the scenario to get the vRealize Operations Manager analysis and assessment of your plan.

Table 1. What-If Analysis Workload Page Options

Option

Description

Add/Remove VMs

Click Add VMs or Remove VMs to create a scenario for adding or removing workload. When clicked, the command displays the Add Workload or Remove Workload screen.

Scenario Name

In the heading of the Saved Scenarios table. Selecting the check box next to the name selects all scenarios in the list and turns on the dimmed Delete button.

Scenario type

Name of the scenario type. Values are Add Workload, Remove Workload, Add Capacity, Remove Capacity, and Migrate.

<scenario_name>

Name of a saved scenario. Selecting the check box next to a name turns on the dimmed Run Scenario,Edit, and Delete buttons.

All Filters

Use the filter to search for a specific scenario by name or type.

Show Columns

Click the small button on the lower left to display the Show Columns dialog box. You can select up to four columns to display in the table: Scenario Name, Scenario Type, Date Created, and Scenario Start and End Date.