Adjusting Cores per Socket in VMware

Suppose you have a Virtual Machine configured with, for example, a single vCPU.  Furthermore,suppose the VM is running on a Host with 4 cores per socket.  By default, the vCPU will only use a single core -- not all 4 cores in the socket!

To enable each vCPU to use multiple cores per socket, you can follow these steps:

1. Power down the VM that you need to change
2. Right click on the VM and select ‘Edit Settings’
3. Select the ‘Options’ tab
4. Click on ‘General’ UNDER the Advanced option
5. Click ‘Configuration Parameters..’
6. Click ‘Add Row’
7. Enter ‘cpuid.coresPerSocket’ in the ‘Name’ column
8. Enter a value (try 2 or 4 in the ‘Value Column’)
9. Click ‘OK’
10. Wait a few seconds while the VM reloads the configuration file.
11. Power on the VM

Source: http://www.virtualizationbuster.com?p=132