Windows 10: Windows 10 and Hyper-V dynamic memory

It seems that Windows 10 does not behave nicely in a Hyper-V virtual machine, also running on Windows 10.

My laptop has plenty of memory and is running Windows 10 build 10586.63.

Normally I configure a new VM with dynamic memory enabled, because I saw no reason why not. Now I found one: Windows 10 as client OS does not like that. All my Windows 10 VM's reported only about 1.5 GB usable with 4 GB configured. Not surprisingly, they were all dead slow.

When I disabled dynamic memory in the settings, the problem went away.

This may severely limit the number of VM's you can be running simultanously!

Bart

:)

 

Recreate Windows 10 Recovery partition

When Windows 10 is installed as a hyper-v virtual machine it creates a 350Mb System Reserved partition at the beginning of the disk and a 450Mb Recovery partition at the end of the disk.

Problem is this 450Mb Recovery partition at the end of the disk then prevents hyper-v edit disk from being able to shrink the dynamic disk!

Solution seems to be either move the 'Recover Partition' or delete and recreate it, question is how?

 

Hyper-V on Windows Home Edition?

In my "Services (Local)", the following are listed:

Hyper-V Data Exchange Service

Hyper-V Guest Service Interface

Hyper-V Guest Shutdown Service

Hyper-V Heartbeat Service

Hyper-V Remote Desktop Virtualization Service

Hyper-V Time Synchronization Service

Hyper-V VM Session Service

Hyper-V Volume Shadow Copy Requestor

Since Hyper V isn't supposed to be on Windows 10 Home, I'm wondering what's going on and why it is in my Services. Are there any other services which would appear in Windows 10 Pro, Enterprise or Education that shouldn't appear in Windows 10 Home Services?

Thanks!

 

Of course a Hyper-V vm becomes slower if you use dynamic memory with default settings. The Hyper-V will be constantly monitoring the demand and assign the required RAM to the vm.

For the dynamic memory to work you need to assign enough startup memory (#1 in screenshot below), increase the the memory buffer (#2) and memory weight (#3):




A Windows 10 virtual machine needs surprisingly little RAM to function well. Here in the screenshot the memory usage of a Windows 10 vm otherwise idle at the moment, only running Macrium to create a system image. Memory demand only 522 MB but because I have assigned a 35% buffer, it's using 768 MB of the assigned maximum 8 GB:




The buffer is important: When using dynamic memory and the demand suddenly increases for example due a resource heavy application being launched, it takes time for Hyper-V to assign more RAM to the vm. The bigger the buffer, the better the vm reacts to increased demand.

Dynamic memory should only be used when it really is needed, for instance when it is important to have multiple virtual machines running at the same time. Dynamic memory should not be used when installing Windows, it can make the time needed for installation somewhat longer.

Generally speaking a Windows 10 vm with 2 GB of static RAM assigned works faster than the same vm with 512 MB to 4 GB dynamic RAM.

 

Thank you for your excellent explanation!

I will keep this in mind, but generally will follow your advice to not use dynamic memory unless I really need it.

Regards,

Bart

 

You are welcome *Smile