Running a Plan on the Current Environment
By default, a new plan mirrors your current environment. It is often instructive to run a plan on your current environment, without making any changes to the plan setup. The results will show how much you can improve your current workload distribution, and whether you should suspend or provision underlying infrastructure to provide a supply that meets the current demand.
If your environment is very large, you can scope the plan to specific clusters or groups and run against those. For information about scoping a plan, see Setting Plan Scope.
The following image shows the results of clicking to run an unmodified plan on the current environment. The results show that the plan suggests you can decommission 2 hosts. This indicates that your environment is overprovisioned, and you can save money by consolidating resources.
In the next image you can see the results of clicking to run an unmodified plan on the same environment, but without respecting constraints such as cluster boundaries or placement rules. In this case the results show that you can decommission 10 hosts and still satisfy the current workload. This indicates the impact that cluster boundaries and other constraints have on the workload placement options that are available to you.