Disable Memory ballooning in a VM

Products

• VMware vSphere ESXi
• VMware vCenter Server

Issue/Introduction

Memory ballooning is a process that allows a physical host to reclaim unused memory from a guest virtual machine (VM), and then allocate it to other VMs that might need it.

It is most beneficial in virtualized environments where there's a significant amount of memory that is assigned but not consistently used across all virtual machines. Thus it optimizes resource utilization.

This article provides steps to disable the balloon driver in a virtual machine.

Environment

VMware vSphere ESXi 7.0.x

VMware vSphere ESXi 8.0.x

Resolution

Note: Disabling the balloon driver in a virtual machine should be performed on case to case basis upon consultation.

Methods to Disable Memory Ballooning:

Method 1 (Reserve all memory):

1. In the VM settings (Edit Settings), navigate to the Resources > Memory section.
2. Set "Reserve all guest memory (All locked)" to "Yes".

Method 2 (Requires VM to be shut down):

1. Shut down the virtual machine.
2. Right-click on the VM and select "Edit Settings".
3. Go to the "Options" tab, then under "Advanced" -> "General" -> "Configuration Parameters".
4. Add a new row with the parameter sched.mem.maxmemctl and set its value to 0.
5. Click OK to save changes.

Additional Information

For more information about Memory Balloon Driver in ESXi 7.0.x 

Memory Balloon Driver

For more information about Memory Balloon Driver in ESXi 8.0.x 

Memory Balloon Driver