Feature pages are design documents that developers have created while collaborating on oVirt.

Most of them are outdated, but provide historical design context.

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MOM Ballooning (Tech Preview)


Introduce automatic memory ballooning as a selectable host or cluster-level policy in order to achieve higher VM density by overcommiting host memory.


Current status

  • Link to feature page in a specific release. That release may complete the feature, or parts of it. The complete scope of this feature in this release will be described in the release feature page
  • Last updated date: 23 October 2012

Detailed Description

This feature covers changes to ovirt-engine, vdsm, and mom to enable a memory ballooning MOM policy at the host or cluster level. For users desiring a high level of VM density even with a risk of degraded performance, an aggressive management policy including memory ballooning is needed. Implementation of this feature can be broken down into the following sub-tasks

  • MOM: Multiple policies support
  • MOM: Per-VM attributes
  • MOM: auto-balloon policy
  • vdsm: API for setting/getting/clearing MOM policies
  • engine: host policy management
  • engine: Policy selection UI

Benefit to oVirt

oVirt will gain the ability to achieve higher VM densities and more efficient use of host memory resources. This feature also serves as the foundation for a more sophisticated SLA framework that will be developed over time.

  • TBD

Documentation / External references

  • TBD