19.6 Settings for the Overcommit Function

The overcommit function can virtually allocate more resources to guest operating systems than the total resources (such as CPU or memory resources) installed on the server.

The overcommit function involves specifying the following kind of settings for CPU and memory:

Item name	Content
CPU clock speed	The maximum amount of CPU resources allocated to virtual servers
Reserved CPU clock speed	The minimum amount of CPU resources guaranteed for virtual servers
CPU allotment ratio	The relative allotment ratio for determining the allotment of CPU resources when multiple virtual servers are competing for CPU resources.
Memory size	The maximum amount of memory resources allocated to virtual servers
Reserved memory size	The minimum amount of memory resources guaranteed for virtual servers
Memory allotment ratio	The relative allotment ratio for determining the allotment of memory resources when multiple virtual servers are competing for CPU resources.

Note

Settings for the overcommit function are required for all L-Server Templates used by this product.
The only virtualization software that supports the overcommit function is VMware or Hyper-V.
For virtual servers where the overcommit function has been enabled, resources will be consumed when the virtual server starts. For this reason, if the settings for reserved CPU performance and reserved memory capacity are less than minimum requirements for the operating system to start, the virtual server may fail to start due to insufficient resources.
Be sure to specify whether to enable or disable the overcommit function before operations commence. This attribute cannot be switched once operations have commenced.

Point

Refer to the following for more information about the overcommit function:

Refer to "Chapter 15 L-Server Template Operations" in the "User's Guide for Infrastructure Administrators (Resource Management)".
Refer to "Creating a Resource Pool" of "Chapter 20 Resource Pool Operations" in the "User's Guide for Infrastructure Administrators (Resource Management)".
Refer to "8.7.1 Display Function Settings for Estimated Price" in the "Operation Guide CE".
Refer to "8.7.3 Metering Log Settings" in the "Operation Guide CE".
Refer to "8.8 System Condition Server List Settings" in the "Operation Guide CE".

How to Use the Overcommit Function

To use the overcommit function, perform the following procedure:

Register an L-Server Template.
Refer to "Chapter 15 L-Server Template Operations" in the "User's Guide for Infrastructure Administrators (Resource Management)" for information on how to create and register L-Server Templates.
Set a definition file.
1. Open the definition file for this product in a text editor.
  The definition file is stored in the following location:
  [Windows Manager]
  [vsys_config.xml]
```
<installation_folder>\RCXCFMG\config\vsys_config.xml
```
  [managerview_config.xml]
```
<installation_folder>\RCXCTMG\MyPortal\config\managerview_config.xml
```
  [Linux Manager]
  [vsys_config.xml]
```
/etc/opt/FJSVcfmg/config/vsys_config.xml
```
  [managerview_config.xml]
```
/etc/opt/FJSVctmyp/config/managerview_config.xml
```
2. Add the following key and value:
  [vsys_config.xml]
  Key name
  Content
  over-commit
  no : Disables the overcommit function (the default value).
  yes : Enables the overcommit function.
  A specification example is shown below:
  Example
```
<properties version="1.0">
    :
  <entry key="over-commit">yes</entry>
```
  [managerview_config.xml]
  Key name
  Content
  enable-overcommit
  false: Disables the overcommit function (the default value).
  true: Enables the overcommit function.
3. Save the file.
4. Restart the manager.
  Refer to "2.1 Starting and Stopping the Manager" in the "Operation Guide CE" for information on how to Restart the manager.
Set item values.
Use the Manager View to set each of the items indicated.
Refer to "8.3.11 L-Platform Reconfiguration" in the "User's Guide for Tenant Administrators" for details on changing the configuration.