vCPU sizing on ESXI 5.0 host

[MikeUNS]

Hello all,

I would like to receive your advices concerning the right vCPU configuration for an ESXI 5.0 host with the following configuration:

CPU: 1* Xeon 5620 Quad-Core HT enabled (server side)

48 GB RAM

here are my calculations: with HT enabled we have 8 cores. As I could read in blogs, we can plan 4vCPU / logical cores. So I can configure a mix of VM with a maximum of 32 vCPU in total (for me, I would never reach this limit).

If I follow my calculations and the customer's needs here is what the host could handle:

VM1 with 4 vCPU

VM2 with 2 vCPU

VM3 with 1 vCPU

VM4 with 2 vCPU

*********************

Total 9 vCPU assigned

Do you think I'm correct, or is it very bad concerning performances or it's not feasible

Thanks for your feedback on this,

Michael

[vRocky]

You should be perfectly fine.

If that first VM needs 4 vCPUs then that is fine, but it is good to be aware that assigning too many vCPUs can actually degrade performance.  It is unlikely with only 4 VMs that this will be an issue for you, but just something to keep in mind.

[sparrowangelste]

most of hte time you can overallocate vcpu, ie have 1-3 machines on a cpu because usually the bottleneck isnt cpu but memory.

of course it depends on your historical needs and future growth...

[MikeUNS]

Hi vRocky and  sparrowangels,

Thanks for your input on this topic. I'm happy to see that I didn't design the server load in a bad way.

This server is intented for SMB with 15 users. 2 of the VMs' will manage the infra (Vcenter + Veeam backup) and the 2 others will serve as production servers.

I will take care of your advices.

Regards,

Michael