FIX: The virtual machine is configured for too much PMEM. 6.0 TB main memory and x PMEM exceeds the maximum allowed 6.0 TB

VMware supports Intel Optane PMem with vSphere 6.7 and 7.0. VMware and Intel worked with SAP to complete the validation of SAP HANA with Optane PMem enabled VMs.

I configured PoC testing VM RAM 1 TB and 1 TB PMem. I was unable to power on. Error – The virtual machine is configured for too much PMem. 6.0 TB main memory and 1024 GB PMem exceeds the maximum allowed 6.0 TB.

Problem was with enable Memory Hot Plug, because there is a limit calculation:

With enable Memory Hot Plug
* Limit 6TB <= size of RAM x 16 + size of PMEM

With disable Memory Hot Plug
* Limit 6TB <= size of RAM + size of PMEM

SAP HANA does not support hot-add memory. Because of this, hot-add memory was not validated by SAP and VMware with SAP HANA and is therefore not supported. According SAP HANA on VMware vSphere

Example how to reproduce an error:

6 TB limit
1 TB PMem
5 * 1024 / 16 = 320 GB

With enable Memory Hot Plug I can't start VM with more than 321 GB RAM.

Author: Daniel Micanek

Senior Service Architect, SAP Platform Services Team at TietoEVRY | vExpert ⭐⭐ | VCIX-DCV 2021 | VCAP-NV Design 2020 | VCAP-DCV Design 2021 | VCAP-DCV Deploy 6 | VCP-DCV 2020 | VCP-NV 2020 | NCIE-DP | OCP | Azure Solutions Architect