Clear Memory after VM reboot

[ondriskamichael]

Hi,

I have 2 identical virtual machines (Windows Servers 2019) running each in different datacenter. They are big SQL servers with 640 GB Memory.

Each VM is running on ESXi host and there is affinity rule that only this VM can run on the ESXi host so no other VM can consume ESXi host memory.

I am experiencing this anomaly when one of the VM clears memory after reboot and it takes lots of time to clear it all and then it boots to OS.

Other VM in the different datacenter does do this action after reboot.

I am not sure what to check so I can see any difference.

ESXi hosts are different models (M640 and R650). I know this can be disabled on physical server in BIOS but this is not possible in VM BIOS which is very limited.

Am I missing something?

Thank you for any help or info.

Michael

[maksym007]

I will say the following: VM (CPU\RAM) usage in VMware is really straightforward. In case you have such problems, I would start to check it from the Hardware level. 

How many CPUs and RAM Modules are on the Mainboard? if all RAM slots are populated with RAM Modules - so a problem somewhere else. Only these two specific VMs making troubles or the rest have the same. How many VMs +\- in the cluster? 

Do you have a resource pool in that Cluster? 

[maksym007]

The worst thing that I can give you the wrong direction - and in a week or two you will figure out that the problem was near your nose and very simple 🙂