Need Advice Assigning Resources to VMs

[wanguy2k]

I have VSphere 5.5 running on the following:

HP Proliant DL380p Gen8

12 CPUs x 2.493 GHz

Intel Xeon CPU E5-2640

Processor sockets     2

Cores per socket     6

Logical processors     24

Memory               148 GB

I'm currently hosting:

Exchange 2010 Server on Windows 2008 server

Domain controller, DHCP, DNS, print server on Windows 2008 server

Application server (lightly utilized)

Voice Mail server on Windows 2008

VMware VCenter Server Appliance

I currently have 32GB memory assigned to the Exchange server, 8 GB each assigned to the others.

I don't know much about processors, cores, or virtual processors.  I took the default one processor and one core per VM when I configured them.  But, as I was configuring the voice mail server the phone consultant was suggesting a quad-core processor, so I assigned 4 CPUs to the server. (I would have assigned

Here's the question: I have 24 logical processors and 148 GB RAM in this box.  Is there a document describing recommended resources for different types of servers, and maybe a description of the effects of adding processor cores to servers?  I don't seem to be having any problems right now but want to make sure I'm getting optimal performance from the VMs.

[DavoudTeimouri]

Hi,

It's recommended that you measure virtual machine CPU usage before assign big resources to that.

For example, you assigned 4 cores to a VM, you should monitor your VM's CPU usage and if it's using more than 80% of its CPU resources and the OS is under pressure when it's working on tasks, you should assign more CPU resources and you can prevent over-sizing on your environment by the way.

You can use ESXTOP or Visual ESXTOP on this regard or use vSphere performance charts.

Anyway, if you don't have any plan for add new VM to this server or your virtual machines are working fine, you can left them without any changes.

[steveb05]

The CPU scheduler is a very complex beast and has undergone some significant changes over the years. Here is a ink to learn how the CPU scheduler works which will help you understand effects you see when/if you change your settings.https://www.vmware.com/files/pdf/techpaper/VMware-vSphere-CPU-Sched-Perf.pdf