What is the most effective stat to show memory used for a VM in vcenter?

Hello,

I'm trying to find a way to really display the amount of memory being used on the GuestOS of a VM inside vcenter.

For example I have VM1
vm1 active memory inside vcenter is .250GB
but VM1 is a DB server and on the box its self it should 8GB used

Because vcenter looks at the active memory pages being used it thinks only .250GB is being used when in reality 8GB is being used by the guestOS.

I'm trying to give metrics to my customers so they can make decisions but I haven't really found a good solution as to how to display the memory.

I was wondering what is considered the best practice

Now for memory as vCenter views it.

Granted= The amount of memory vCenter presents to the VM/Guest. This is the amount of “physical” memory the guest believes it has.

Consumed=”..the amount of machine memory allocated to the virtual machine, accounting for the savings in shared memory.”

vSphere Resource Management Guide page 34 on Active Memory
Active= “ESX uses a statistical sampling approach to estimate the aggregate virtual machine working set size without any guest involvement. At the beginning of each sampling period, the hypervisor intentionally invalidates several randomly selected guest physical pages and starts to monitor the guest accesses to them. At the end of the sampling period, the fraction of actively used memory can be estimated as the fraction of the invalidated pages that are re-accessed by the guest during the epoch. ESX uses a statistical sampling approach to estimate the aggregate virtual machine working set size without any guest involvement. At the beginning of each sampling period, the hypervisor intentionally invalidates several randomly selected guest physical pages and starts to monitor the guest accesses to them. At the end of the sampling period, the fraction of actively used memory can be estimated as the fraction of the invalidated pages that are re-accessed by the guest during the epoch.”

In layman’s terms, vCenter and Esx/Esxi have a really complicated algorithm for calculating how much of the memory is actively, yes actively being used by the guest.

The issue names no source file, test, or entry point and asks for best-practice guidance on displaying guest memory usage in vCenter. First clarify whether the request is for pyvmomi to expose a metric; completion criteria are not defined in the current report.