How to correctly configure my host server

[loikk]

Hello,

I plan to buy a server to install proxmox (with local storage) on which I plan to run a dozen virtual machines (Windows and Linux)

And I wonder how to choose the physical processor, quantity, number of cores etc

Does a vCPU correspond to a physical core?

In which case, if I plan to allocate 2 vCPUs to my 10 VMs, should I buy a server with at least 20 physical cores?

Thank you for your answers

 

[t.lamprecht]

Hi,

one thing to look out for is: never overcommit memory, be sure that there's enough for all VMs and the host (1-2GB).

Does a vCPU correspond to a physical core?

I mean yes, there cannot run more vCPU concurrently as the host provides cores, but that does not mean that you cannot use more vCPUs. If more want to run at the same time they will get scheduled in a fair way. How much vCPUs you actually want to "overcommit" depends a lot on what the VMs need to do, i.e., their workload. Often VMs do not have permanent load on all their vCPUs in that case it would be very inefficient to have a 1:1 mapping of host CPUs to vCPUs.

 

[zezinho]

You are starting virtualisation without understandind it. You can allocate 20 cores to all the VMs with a server which has 20 physical cores. Of course, the problem will be the load : if all VMs are using 100% CPU, you'll get only single core performance.

TLDR : you can buy a server with at least the biggest VM cores count if the load in any VM is small.

 

[t.lamprecht]

See also https://pve.proxmox.com/pve-docs/chapter-qm.html#qm_cpu

 

[loikk]

See also https://pve.proxmox.com/pve-docs/chapter-qm.html#qm_cpu

thx for your reply