One of the discussions when designing a Hyper-V server is about the pagefile settings.

The pagefile is used for:

  • Supply Virtual Memory to the operating system (i.e. the parent partition). Traditional guidance states ~1.5x the amount of physical memory, although this doesn’t make sense anymore on a >64GB host;
  • Crash dump purposes, but on a hosts with lots of memory (more than 64GB) do you want to have a full memory dump? Look at the number of hours this memory dump will take and you’re convinced that for 98% of all cases a kernel dump is sufficient.

Normally the parent partition uses around 2GB of memory (recommendation) so I usually recommend a manually managed pagefile of approximately 4 ~ 6 GB. Why not a system managed pagefile? Because it will grow to the amount of physical memory.

To change this on a Hyper-V Server Core or Hyper-V Server you can use the following commands:

wmic computersystem set AutomaticManagedPagefile=False
wmic pagefileset where name=”c:\\pagefile.sys” set InitialSize=4000,MaximumSize=6000

It is possible to check the pagefile settings using the following command:

wmic pagefile get /format:list

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Or you can use the Registry Editor (Yes, this is available on Hyper-V Server and Server Core) and navigate to
HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management

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