Got it

[Feature] Smart Memory Overcommitment

Latest reply: Jul 4, 2022 07:45:16 2017 8 6 0 0

Hello, everyone! Now I'd like to share with cloud feature - smart memory overcommitment. 

This feature allows a server to provide virtual memory that can be larger than the server's physical memory size using various memory technologies, such as memory ballooning, memory sharing, and memory swapping.

cloud feature

1. Definition

Memory overcommitment allows a VM to use more memory space than the physical host has. Commonly used technologies include memory ballooning, memory sharing, and memory swapping. This feature allows more VMs to be supported by a server since it offers more memory resources than the physical server has.

This feature increases memory utilization, reduces the investment on storage devices, and prolongs the memory service time for servers.

FusionCompute supports the following memory overcommitment technologies:

  • Memory ballooning: The system automatically reclaims the unused memory from a VM and allocates it to other VMs to use. Applications on the VMs are not aware of memory reclamation and allocation. The total amount of the memory used by all VMs on a physical server cannot exceed the physical memory of the server.

  • Memory swapping: The system swaps out the content on the reserved VM memory to an external storage file to free the reserved memory and gets back the content when required.

  • Memory sharing: Multiple VMs share the memory page on which the data content is the same.

The memory overcommitment degree is inversely proportional to the actual VM memory usage. Therefore, you must specify the QoS of the memory overcommitment for compute nodes.

After memory overcommitment is enabled, the memory overcommitment policy is used to allocate memory. VMs can use all physical memory when the memory is sufficient. If the memory is insufficient, the system schedules memory resources based on the memory overcommitment policies using memory overcommitment technologies to release free memory.

2. Enabling Memory Overcommitment for a Cluster

1. In the navigation pane, click Resource Pools.

   The Resource Pools page is displayed.

2. On the Cluster tab page, click the cluster to be configured.

    The Summary tab page is displayed.

3. On the Configuration tab page, choose Configuration > Control Cluster Resource.

4. In the right pane, click Edit.

    A dialog box shown in Figure 1 is displayed.

    Figure 1 Control Cluster Resource

Control Cluster Resource

5. On Basic Configuration, click On to enable Host Memory Overcommitment.

If the function is enabled successfully, go to 7.

If the function fails to enable and a message is displayed, indicating that the function cannot be enabled because the size of the host memory partition cannot meet the conditions for enabling memory overcommitment, go to 6.


After the host memory overcommitment function is enabled, you can configure memory overcommitment by setting VM memory QoS, including quota, reserved (MB), and limit (MB).

To disable the host memory overcommitment function, the memory overcommitment ratio for each host in a cluster must be less than or equal to 100%. For details about how to query the host memory overcommitment ratio, see Configuring the Host List Display Options.

After the host memory overcommitment function is disabled, the total memory of all VMs running on each host cannot be greater than the total physical memory actually available to the VMs.

6. Add memory swap partitions for hosts that do not meet requirements by performing the operations provided in Adding a Memory Swap Partition to a Host. Then, go to 5.

7. Click Confirm.

The host memory overcommitment function is enabled.

3. Related Alarms

ALM-15.1003888 Host Memory Overcommitment Exceeds the Threshold

ALM-15.1004046 The maximum memory overcommitment rate of the host is less than 100%

This is what I want to talk/share with you today, thank you!

  • x
  • convention:

Admin Created Feb 26, 2020 14:26:55

  • x
  • convention:

Created Feb 27, 2020 06:34:09

View more
  • x
  • convention:

Created Feb 27, 2020 06:37:34

[Feature] Smart Memory Overcommitment-3231126-1
View more
  • x
  • convention:

Created Feb 28, 2020 20:16:43

View more
  • x
  • convention:

Created Mar 1, 2020 17:45:45

Wow, Nice.
View more
  • x
  • convention:

Created Mar 15, 2020 03:43:01

[Feature] Smart Memory Overcommitment-3243000-1
View more
  • x
  • convention:

HCIE Created Jul 4, 2022 07:45:16

[Feature] Smart Memory Overcommitment-5031223-1
View more
  • x
  • convention:

olive.zhao Created Jul 5, 2022 08:37:39 (0) (0)


You need to log in to comment to the post Login | Register

Notice: To protect the legitimate rights and interests of you, the community, and third parties, do not release content that may bring legal risks to all parties, including but are not limited to the following:
  • Politically sensitive content
  • Content concerning pornography, gambling, and drug abuse
  • Content that may disclose or infringe upon others ' commercial secrets, intellectual properties, including trade marks, copyrights, and patents, and personal privacy
Do not share your account and password with others. All operations performed using your account will be regarded as your own actions and all consequences arising therefrom will be borne by you. For details, see " User Agreement."

My Followers

Login and enjoy all the member benefits


Are you sure to block this user?
Users on your blacklist cannot comment on your post,cannot mention you, cannot send you private messages.
Please bind your phone number to obtain invitation bonus.
Information Protection Guide
Thanks for using Huawei Enterprise Support Community! We will help you learn how we collect, use, store and share your personal information and the rights you have in accordance with Privacy Policy and User Agreement.