Manually increasing the heap memory of components in vCenter Server 6.x, 7.x and 8.x

Products

• VMware vCenter Server

Issue/Introduction

This article provides steps to increase the heap memory of individual vCenter Server components to resolve performance issues in components such as the vSphere Web Client/vSphere Client.

Symptoms:

• Performance issues in components such as the Inventory Service and vSphere web-client/vSphere client.
• Services such as the vsphere-client's status changes from green to yellow continually.

Environment

VMware vCenter Server 6.x.
VMware vCenter Server 7.x.
VMware vCenter Server 8.x.

Cause

Heap memory of vCenter components becomes exhausted.

Resolution

Depending on whether you are using a vCenter Server Appliance or a Windows vCenter Server, please see the relevant steps below.

Note: Service names may vary between vCenter Server versions 6.x,7.x and 8.x. As such, please see the article below for service names and how to stop and start services in vCenter Server Appliance and Windows Center Server.

Stopping, Starting or Restarting VMware vCenter Server Appliance 6.x & above services (2109887)

 

Important: Updates of vCenter server may revert these changes, so document accordingly and as needed to repeat this process.

 

vCenter Server Appliance:

1. Use SSH to connect to the VCSA as root and enter the Bash shell by typing shell and pressing Enter
2. Run the following command to output memory assigned to each of the services:

cloudvm-ram-size -l

 

3. Increase the amount of memory assigned to the services by running the following command, using the vCenter HTML5 web client (or "vsphere-ui"), as an example:

cloudvm-ram-size -C XXXX vsphere-ui

Note: XXXX should be replaced with the desired amount of memory in MB.
For example, this command would increase the memory of the vsphere-ui service from 768 MB to 2048 MB.

 

cloudvm-ram-size -C 2048 vsphere-ui

There is no "one size fits all" memory value to set in this scenario, however - as a guide, double the size of currently assigned memory of the service that has an issue. This may need to be repeated.
 

4. Restart the service that has been altered, in this example - vsphere-ui:

service-control --stop vsphere-ui;service-control --start vsphere-ui;
 

5. Confirm that the service has now been allocated the increased memory by using this command:

cloudvm-ram-size -l

Windows vCenter Server:

1. Open a command prompt to the following location:

C:\ProgramFiles\VMware\vCenter Server\visl-integration\usr\sbin\
 

2. Run the following command to output the services and heap memory assigned to them:

cloudvm-ram-size.bat -l

 

3. Run the following command to modify the service memory using the vCenter HTML5 web client (or "vsphere-ui"), as an example:
   cloudvm-ram-size.bat -C XXXX vsphere-ui
    
   Note: XXXX should be replaced by the desired amount of memory in MB.
   For example, this command would increase the memory of the vsphere-ui service from 791 MB to 2048 MB.
    
   cloudvm-ram-size.bat -C 2048 vsphere-ui
    
   There is no "one size fits all" memory value to set in this scenario, however - as a guide, double the size of currently assigned memory of the service that has an issue. This may need to be repeated.
4. Restart the service that has been altered using command prompt or via Services in Windows.
5. Confirm that the service has now been allocated the increased memory using the command:

cloudvm-ram-size.bat -l