Enabling Dynamic Memory

If you have not tried out dynamic memory yet – here is a handy step-by-step guide for how to get it setup.
The first thing you need to do is to install the Windows Server 2008 R2 SP1 beta release.  To do this you should:

1. Download the beta from here: http://www.microsoft.com/windowsserver2008/en/us/sp1.aspx
2. Shutdown any virtual machines before installing the service pack in the parent partition
   • Saved states and snapshots from Windows Server 2008 R2 RTM are compatible with the SP1 beta release – so there is no need to discard them.  Note – this may not be the case with the SP1 RTM release.
3. Apply the service pack
4. Reboot the physical computer

At this stage you will have the service pack 1 beta applied to your system – but you will not have enabled dynamic memory for any of your virtual machines.  There are two main steps to enabling dynamic memory.
Step 1: Upgrading the integration services inside the virtual machine

Dynamic memory needs new integration components to be installed in the virtual machine.  If you are running Windows Server 2008 R2 or Windows 7 inside of the virtual machine you can do this by either upgrading the integration services or by just installing the service pack 1 beta inside the virtual machine as well.  For all other supported operating systems you will need to upgrade the integration services.  To do this you will need to:

1. Boot the virtual machine
2. Connect using the Virtual Machine Connection window from the Hyper-V manager
3. Log in with an account that has local administrator rights on the virtual machine
4. Open the Action menu and select Insert Integration Services Setup Disk
   
5. Depending on the guest operating system you are running – you may need to select to start the integration services installer (or it may run automatically)
   
6. When prompted to upgrade the Hyper-V integration services – click OK
   
7. When the installation is completed and you are prompted to reboot – click No
   
8. Now shutdown the virtual machine

The next step is to enable dynamic memory in the virtual machine settings.  To do this the virtual machine needs to be turned off, which is why you needed to shutdown the virtual machine instead of letting it reboot.

Step 2: Enabling dynamic memory in the virtual machine settings
Once the virtual machine is no longer running, you will need to:

1. Open the virtual machine settings
2. Change to the Memory page
3. Select the Dynamic option
4. Set the Startup RAM to be as low as is necessary for the virtual machines guest operating system to boot.  512mb is a good figure to choose for most operating systems
5. Set the Maximum RAM to an appropriate value (it will default to 64GB of RAM – and for many people this will be fine.  All of my virtual machines have a maximum RAM value of 64GB)
6. Hit OK
   

You can now start the virtual machine.  You should be able to tell when dynamic memory starts functioning inside the virtual machine as you will see a percentage getting reported in the Memory Available column for any virtual machine which has dynamic memory enabled.