Page file Size on Hyper-V server

System Manged will make it over 150GB no?

Correct, see this article, written by the Top Expert Mark Russinovich

Pushing the Limits of Windows: Virtual Memory

Andrew, I just skimmed that link and does not give any recommendations??

If you read the document it states:-

How Big Should I Make the Paging File?

To optimally size your paging file you should start all the applications you run at the same time, load typical data sets, and then note the commit charge peak (or look at this value after a period of time where you know maximum load was attained). Set the paging file minimum to be that value minus the amount of RAM in your system (if the value is negative, pick a minimum size to permit the kind of crash dump you are configured for). If you want to have some breathing room for potentially large commit demands, set the maximum to double that number.

Source
http://blogs.technet.com/b/markrussinovich/archive/2008/11/17/3155406.aspx

and if you read through the comments, a Microsoft employee, stats System Managed, and explains how Microsoft came to that conclusion.

Hence why I typed System Managed in my first post, with this reference to support it.

So I'll repeat again, set it and leave it at System Managed.

OR, if you want to do some homework, follow Marc's advice....

Personally, we leave the System to Manage it. e.g. System Managed.

You could create another RAID Array/Logical Disk/Virtual Disk for the Pagefile, e.g. move from the OS disk.

So Andrew,  will I have a >150GB Pagefile?
If so this seems wrong as the server does not need to page the virtual computers that need the ram.
thanks

Please see this Article.... by Aidan Finn, if you have not heard the name, a Microsoft Evangelist, specially around Hyper-V.

http://www.aidanfinn.com/?p=15659

Now the official line on the paging file is:

For Hyper-V servers that run Windows Server 2012 or Windows Server 2012 R2, the page file should be left at the default of setting of System Managed. This is per the Hyper-V Product Group.

Source
http://www.aidanfinn.com/?p=15659

So again, System Managed. by default.

For Windows Server 2012 Hyper-V and Windows Server 2012 R2 Hyper-V, the page file of the management OS (commonly called the host OS) should be left at the default of setting of "System Managed." This is per the Hyper-V product group.

Source
Microsoft Kb Article

And is this true for Win 2008 R2?

Yes, the same is true. Let the System Manage it.

I have an EE article here: Some Hyper-V Hardware and Software Best Practices.

In there you'll see the note that we set a static swap file to 4192MB.

There are several reasons for this.

 1: Cluster hosts have an 80GB RAID 1 SSD while they can have 128GB, 256GB, 512GB, or more physical RAM
 2: Standalone hosts are set up with two partitions. OS goes into 75GB or less
 3: A Hyper-V host should _never_ need the swap file for actual swap work
 4: Set MiniDump instead of Full Dump (a reason for leaving System Managed)

In today's environments where hosts have well past 256GB of RAM it does not make sense to size the system partition according to the amount of RAM just for the swap file.

As a side note, we've been using this setup since 2008 RTM and have had no issues with swap file usage nor troubleshooting as the host would leave behind the MiniDump (if not hardware related full-stop) with enough info in there to troubleshoot.

That's not what the Hyper-V Group Recommend,  and we've been doing the same and we have no issues! We leave as System Managed, and it manages it!