How does Hyper-V manage the core allocation with an Intel i9-13900(k)?

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Hi, I'm planning to build a new PC where I have to run multiple virtual machines at the same time.

I was thinking to use an i9-13900 (k or not) because of its 24 cores but I just realized that it has Performance Cores and Efficiency Cores so how does HyperV manage the core allocation with such architecture?

And another thing about the core allocation that I didn't understand very well is if I can allocate to a virtual machine only up to the maximum number of cores of the CPU, for example I actually have a CPU with 4 cores and 8 threads so I can allocate up to 4 cores or can I go beyond 4 until I reach 8 because it has 8 threads?

Thanks for the help.

A Windows technology providing a hypervisor-based virtualization solution enabling customers to consolidate workloads onto a single server.
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  1. Limitless Technology 44,011 Reputation points

    Hello there,

    A virtual machine’s vCPU count means the maximum number of threads that the VM can run at any given moment.

    Generally, it's recommended to set 8 vCPUs per 1 physical core.

    This article describes Hyper-V resource and isolation controls for virtual machines. These capabilities, which we'll refer to as Virtual Machine CPU Groups, or just "CPU groups", were introduced in Windows Server 2016.

    Hope this resolves your Query !!

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  2. Dave Patrick 426.1K Reputation points MVP

    You can over-allocate up to a point. Read on here.


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  3. Dave Patrick 426.1K Reputation points MVP

    If you try to allocate more cores than the host has you'll get something like below when you try to start it up.

    User's image

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