Can only have 1 VM running at a time


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I have been using a Windows8 VM for a while and don't have any issues.

 

I am installing Windows10, and have completed the installation. 

 

My issue is if I start my Windows10 VM, my Win8 VM stops without me telling it to.

 

I want both to run at the same time, what settings might I have wrong?  They are both using network br0, could that be causing an issue, should I move one to br1?

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I have 20 gigs, with each VM given 8 gigs.

 

There is a bit of overhead with each VM but that should be enough.

Maybe trying setting each VM to 4GB and try again.

 

That did the trick.  Guess I have to add more RAM to my server to give each VM 8gigs.

 

I have 4 cores, any issue with assigning all four to each VM, or should I split them up 2 each?

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That did the trick.  Guess I have to add more RAM to my server to give each VM 8gigs.

 

I have 4 cores, any issue with assigning all four to each VM, or should I split them up 2 each?

 

There is a bit of overhead on each VM.

If you run "free -m" in the unRAID console after you've started one of the VM's you can get a look at exactly how much RAM has been used.

 

As far as I know you can assign all four to both and they will share but I'm not 100% sure with KVM.

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VMs are currently pinned to physical CPU cores. You select which cores to assign them based on the total number of cores in your processor. This quantity is doubled the physical core count when a processor include hyperthreading support (e.g. a dual core HT processor gets 4 cores).

 

If you are hosting a VM designed as an application server (say an arch linux VM for installing your own apps in lieu of Docker), letting it and other server VMs run in a shared set of CPU cores. You can probably even overlap them with any CPU cores you pin your containers as well, and KVM/QEMU route the traffic. In a future iteration, this will work a little differently, but not for short term.

 

What's important to note is that if you intend to run a high performance workstation or gaming rig, you will want to isolate that VMs CPU cores from any other VMs or Containers on the system. Example:

 

With 8 cores available for assignment, you can do a 50/50 config between containers and server VMs (cores 0-3) and then 1 active desktop VM (cores 4-7) for smooth operation.  This prevents context switching from occurring in the CPU which eliminates interrupts in processor access that would be detrimental to real time performance needs.

 

If you want to go really aggressive, another valid configuration will be to assign 0-1 to containers/server VMs and 3-7 to the desktop VM. But again, we are talking high performance here. The good thing about VMs is that you can toy with these configurations with a VM to figure out the right balance for your needs. We have some interesting ideas for the roadmap on how to enable some auto optimization for containers and VMs as well.

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