Windows Server 2008 R2 guest: pagefile issue

[MariusRoma]

I have several Windiows Server 2008 R2 guests.

What is the best way to dimension and place the Windows page file?

For physical Windows Servers many people suggest to allocate a fixed size page file whose size is 1,5 times the RAM: does it make sense for hosted VMs as well?

Is there any best practice or guideline to refere to?

Regards

marius

[vmroyale]

I tend to use the 1 or 1.5 x RAM rule for starters, even though the logic is flawed: http://blogs.technet.com/b/markrussinovich/archive/2008/11/17/3155406.aspx

Other than sizing, replication and performance are the other considerations.

[jrmunday]

Hi Marius,

Prior to Windows Server 2008 I have always set both values (Initial and Max) to 1.5x physical RAM, making no distinction between physical or virtual. On Win2k8 and above I find that the OS does a much better job of managing it's own pagefile (including shrinking it) so I would go with "System managed" in your case.

Cheers,

Jon

[rickardnobel · Accepted solution]

Marius - Roma wrote:

What is the best way to dimension and place the Windows page file?

For physical Windows Servers many people suggest to allocate a fixed size page file whose size is 1,5 times the RAM: does it make sense for hosted VMs as well?

Is there any best practice or guideline to refere to?

As noted by A.P. the 1.5 x RAM is really just an arbitrary number someone at Microsoft came up with at some moment and then has entered the best practices without no real valid reason.

However, there could be some things to concider:

Leave it to system managed is the most simple way, but could lead to higher fragmentation of your C: drive.

If setting a fixed size you should really concider how much space you like Windows to be able to push into the pagefile with internal memory overcommit. Typically if the Windows machine have a  decent amount of RAM then the page file usage it quite low.

If adding another virtual harddrive to the VM and put the pagefile.sys on that you have a little more complex setup, but might get savings if possible to exclude that drive in your backup tool and VM replication settings (if used). You could also possible put all VM guest files on some kind of thin provisioned LUN/NFS since it will consume lots of space, but be used very little.