Running the dmidecode command on Redhat Enterprise Linux virtual machines returns more CPUs than what is provisioned

Products

• VMware vSphere ESXi

Issue/Introduction

• When running the dmidecode command on the Redhat Enterprise Linux virtual machines, more CPUs than what is provisioned are returned.
   
• The dmidecode command displays the maximum supported CPUs for the virtual machine operating system.

Environment

• VMware vSphere ESXi 5.5
• VMware vSphere ESXi 5.1
• VMware vSphere ESXi 6.0
• VMware vSphere ESXi 5.0

Cause

This issue occurs when using legacy BIOS option when creating the virtual machine. The virtual machine is created with CPU entries for the maximum amount of CPUs (64 or 128) even if they are not in use. Running the dmidecode command will return all the entries provisioned to the virtual machine, not only the CPUs in use. This issue does occur with Extensible Firmware Interface (EFI).

Resolution

This issue is resolved in ESXi 6.5.