VMs > Cores in Xen possible?

As someone who has been experimenting with XCP-NG for a few years, I’ve encountered a fundamental question to which I haven’t found a direct answer. Despite my efforts, I have yet to achieve this through my experimentation.

Can I have more running VMs than physical cores in XCP-NG?

For a minimal example, let’s assume I have an eight-core processor and eight one-core VMs active. Can I start a ninth VM? Or are Xen machines always limited to |VM| =< |Cores|?

Type 2 hypervisors have allowed me to allocate more VMs than cores, but I’ve been grappling with achieving this concept with Xen as a Type 1 hypervisor. I’ve delved into the confusing documentation for hardware virtualisation and paravirtualisation, pouring hours into the topic, yet the solution remains elusive.

I greatly appreciate any assistance you can provide on this matter. Thank you in advance.

Yes, you can over provision them but there are things to consider which is why I made a video on the topic.

Thank you. The term “over provision” was the part I was missing in my Google searches. Thank you, as always; I really appreciate your videos.

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