For precise control over the amount of memory allocated for the VMware Identity Manager service, you can change the memory allocated in Tomcat through the Windows system properties environment variables page.

When the VMware Identity Manager service is installed, the default is to set the memory setting to be half of the available memory. Usually the default setting does not need to be changed.


  1. On the VMware Identity Manager Windows machine, open the Control Panel and navigate to Systems Properties > Advanced tab.
  2. Click Environment Variables at the bottom of the dialog box.
  3. In the Environment Variables > User Variables section, click New.
  4. In the New User Variable dialog box, enter the variable as IDM_TOMCAT_MEM= <#>g

    #g is the memory to allocate. 2G is the minimum memory setting to allocate, but there is no maximum.

  5. Restart the service. Type the batch file command, horizonService.bat restart.