Recent academic research has demonstrated that it is theoretically possible to leverage TPS to gain unauthorized access to data under certain highly controlled conditions. For more information, see https://blogs.vmware.com/security/2014/10/transparent-page-sharing-additional-management-capabilities-new-default-settings.html.

For this reason, in vSphere 6.x, TPS is disabled across different VMs, but is still working inside individual VMs. It is still possible to enable it on the entire ESXi, by following KB 2097593—Additional Transparent Page Sharing management capabilities and new default settings at https://kb.vmware.com/kb/2097593.