Workloads are often placed suboptimally, resulting in the inefficient use of clusters and chronic resource contentions. Resolving contention by balancing resources is a difficult, time-consuming, and nonstrategic activity.

Using vRealize Operations Intelligent Workload Placement, you can visualize how your workloads are distributed and used across the environment, and you can see trends. When the workload in your environment becomes imbalanced, Intelligent Workload Placement recommends rebalance actions to resolve resource contention and improve performance of applications and infrastructure:

Intelligent Workload Placement determines the best destination to run your workload by rebalancing existing workloads inside a container. The container for the rebalance action can be a data center or a Custom Data Center (CDC). Intelligent Workload Placement provides you with a prioritized list of recommended places to put or move the workload.

A custom data center can be used to perform capacity management and planning across disparate groupings of capacity providers. You can associate all the Analysis Badge data for these groupings. Using custom data centers, you can group various capacity provider objects such as hosts, clusters, virtual data centers, and VMware vCenter Server® instances. These objects might span multiple vCenter Server instances.

VMware vSphere's Distributed Resource Scheduler (DRS) plays several, very important roles within VMware vSphere.

It can decide where to deploy a new VM, or move an existing VM, within a cluster to ensure virtual machines are always running on a host with adequate resources to support it. It can also help migrate VMs off a host when we place it in maintenance mode:

However, there are some limitations to what DRS can do on its own. For example, because DRS can only move VMs between hosts within a cluster, there's very little that it can do when that cluster runs out of resources. Once a cluster has been completely utilized, vSphere DRS cannot move the workloads to other underutilized clusters in the data center or Custom Data Center.

Question: Can we allow DRS to move VMs between clusters or to move VMs before resource contention even occurs?

The answer is, yes! vRealize Operations allows us to do this:

vRealize Operations enhances vSphere DRS further by providing the Rebalance Container feature, which moves virtual machines between clusters, thus ensuring that the clusters are balanced in the environment.

The vRealize Operations rebalance feature works with vSphere DRS to help virtual machines get the required resources:

• vRealize Operations determines how to best balance clusters within the CDC or the data center:
  • Creates a rebalance plan recommending the migration of virtual machines from overutilized clusters to underutilized clusters
  • Moves virtual machines to the underutilized clusters
  • Hands over the virtual machine to vSphere DRS
  • vSphere DRS can then optimally balance virtual machines within a cluster by determining the best host in the cluster to place the virtual machine