Home > Microsoft, Virtualization > Hyper-V Windows 20012 improvments and comparison

Hyper-V Windows 20012 improvments and comparison

Significant improvements have been made across the board, with Hyper-V now supporting increased cluster sizes, a significantly higher number of active virtual machines per host, and additionally, more advanced performance features such as in-guest Non-Uniform Memory Access (NUMA).

The tables below shows the improvement Microsoft has done with  Windows 20012 Hyper-V :



The table also shows that both Windows Server 2012 Hyper-V and vSphere 5.0 Enterprise Plus deliver up to 1TB of memory to an individual virtual machine, however, one aspect to bear in mind when creating virtual machines of this size, is the vRAM (Virtual Machine Memory) entitlement with vSphere 5.0.

  • Each vSphere 5.0 Enterprise Plus CPU license comes with a vRAM entitlement of 96GB vRAM, and on a 2 CPU physical host, this would equate to 192GB vRAM added to a ‘vRAM Pool’
  • The 1TB virtual machine would consume 96GB of the vRAM allocation (this is an upper limit established for an individual VM, and was one of the results of customer feedback around the original vRAM licensing announcements)
  • This would leave only 96GB of vRAM for use by other virtual machines, restricting scale. The only option to overcome this would be for the customer to purchase additional vSphere 5.0 licenses at considerable expense. This is on top of the extra administrative overhead of monitoring and managing vRAM entitlements.



1.XenServer 6.0 active VMs per host varies based on Server/VDI workload, with PVS/IntelliCache & HA on/off
2.Maximum VMs on a Cluster (Resource Pool) on XenServer 6.0 based on a maximum of 50-60 concurrent protected VMs per host with HA enabled.
3.Host physical memory is capped at 32GB thus maximum VM memory is also restricted to 32GB usage.
4.For clustering/high availability, customers must purchase vSphere
5.vSphere 5.0 Enterprise Plus is the only edition that supports 32 vCPUs.  All others support 8 vCPUs within a virtual machine.
6.Maximum number of Virtual CPUs per Host is not documented in the Citrix XenServer 6.0 Configuration Limits documentation
  1. donald.kennedy@northgate-is.com
    November 29, 2012 at 21:20

    ESXi 5.1 is the latest release and the vRAM entitlement has been removed for Enterprise & Enterprise Plus

  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: