“Balancer” in VMmanager for automatic load distribution

“Balancer” in VMmanager for automatic load distribution

Congestion of nodes can cause failures in the operation of services that are located on these nodes. The new VMmanager service – “Balancer” – monitors the load and distributes virtual machines across nodes within the cluster, preventing problems from occurring. At the same time, the administrator only needs to set the settings – VMmanager will do the rest for him. We tell you how the new service works.

Collection of information about the load of nodes

To understand how this or that node “feels”, the “Balancer” requests data on the average load of CPU and RAM for a set period. This option is set by the administrator. If 10 minutes is specified in the “check frequency” field, the service will request statistics for the last 10 minutes.

It takes about one minute to collect information. If there are a lot of nodes, this time may not be enough. Then the “Balancer” will work only with the data it managed to collect and draw a conclusion based on it. A list of VMs on nodes that failed to be verified will go into the beam.

Analysis of received information and preparation for migration

After collecting statistics, the “Balancer” divides the nodes into two groups:

  • overloaded – by default, the node is considered overloaded if the CPU and RAM are “clogged” by 70%, but if necessary, the administrator can change these limit values;

  • nodes with a light load.

Nodes that are in the process of maintenance are not included in the group.

Then the service compiles a list of VMs that can be migrated from the loaded node to a freer one. At the same time, the administrator can leave certain VMs on the current host and not apply service actions to them.

If the Balancer does not find overloaded nodes or nodes to which the VM can be migrated, the migration will not occur.

After a set period of time, the service will repeat the entire algorithm of actions.


The “Balancer” will transfer VMs between nodes using the live migration mechanism (without stopping them) – they will be available throughout the transfer procedure. Migration is available within a cluster.

For more information on how to set up the service, VMmanager documentation.

To test the capabilities of VMmanager personally, order a demo or free 30-day trial.

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