optimal ESXI configuration for host with 50 virtual Windows 7 PCs?

[bbowman]

I'm looking to dial in my EXSI 5 host configuration to provide optimal performance for the 50 Windows 7 PCs that are running on this host.  Not all Win7 VMs are used at the same time, I'd say that a maximum of 5-7 are used concurrently.

Using an internal datastore on the host and each VM is thick provisioned.  Currently each VM has 1 CPU allocated to it along with 1gb of RAM.  Is it best to set a memory reservation for each host?  Is there a CPU allocation method that I should be using?

Let me know if there are any configuration details that I should post that would be helpful in determining whether or not something should be changed.

[ClintColding]

Are your VM's running into contention issues with either RAM or CPU? What are the specs of the physical host?

[bbowman]

What do you mean contention issues?  Do you mean do they ever max out?  If so, no.

The host is a Dell PE R900 with 2x Xeon E7420 processors and 48gb of RAM.  I misspoke, there are 39 Win7 VMs on this host, not 50.

[ClintColding]

By contention, are the VM's maxing out the physical resources of the host. In your case it doesn't sound like they are.

Reservations reserve resources for a VM. Reservations are helpful if your host is experiencing contention and you have a particular VM that you'd always want to have a certain amount of RAM available to it.

VMware vSphere - Reservations

Here is a solid description of shares:

Shares specify the relative importance of a virtual machine (or resource pool). If a virtual machine has twice as many shares of a resource as another virtual machine, it is entitled to consume twice as much of that resource when these two virtual machines are competing for resources.

VMware vSphere - Shares

Both are good to set before you begin experiencing contention so that your most critical VM's aren't affected. However, if you aren't experiencing contention, these configurations won't impact performance.

[bbowman]

All of the VMs on this host are equally important.  Are there any other 'best practice' configurations for an EXSI 5 host with 40 VMs?

[ClintColding]

You shouldn't see contention issues with your current configuration because you haven't overcommitted your physical resources. The biggest factor in performance configuration would probably be how your storage is configured, other than that for 40 1x1 VM's everything is fine. What are these VM's used for?

[bbowman]

These Win7 VMs are used by our support staff.  Each of these VMs are specifically configured to connect to customers of ours using VPN clients that they provide.  Often these PCs respond sluggishly so I was hoping there was a more optimal way to allocate CPU/RAM resources.  Any other ideas?

[ClintColding]

You could try allocating more RAM to the VM's themselves. Try increasing to 2GB to see if you get a performance increase.