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roy_battyFlag for United Kingdom of Great Britain and Northern Ireland

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How many vCPU to asssign to my VMs

I have a Server 2012 R2 running on a HP Proliant Server. The server has 2 x Intel Xeon E5-2620 v3 @ 2.40 Ghz Processors.

It is running Hyper-V with two guest OSes. Both Server 2012 R2.

My questions is how many processors do I assign to each VM to get best performance.

One of the VMs is running SQL Express which I think is limited to running on servers with just one processor. How should I assign processors here?

These processors have 6 cores, is that classed as 6 processors? I really am unsure here.

Thanks
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it_saige
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OK Thanks. I will be sign SQL Express 2012.

To clarify one VM is a DC for 35 users and will also be running SQL EXpress.

The 2nd VM is an RDS server publishing one application to 5 users.

Currently the VMs are set to "1" Processor each. What numbers should I put in this field presuming I am splitting the processing power 50/50 between VMs?

Is it 2 in each as the physical server has 2 physical processors or is it 12 in each, you said it had 24 cores in theory?

I
Each Intel Xeon E5-2620 v3 has 6 physical cores.  Using hyper-threading, each physical core is treated as two logical cores.  6 x 2 x 2 = 24.

Read more about Hyper-Threading here.

I wouldn't worry so much about a 50/50 split in processing power.  Without knowing the setup of the hardware you actually have, I would say 4 cores per vm would probably be sufficient with 6 - 8 cores representing the sweet spot.  Anything more and you are most likely talking about overkill or mismanagement of resources.

-saige-
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For more information and perhaps a better explanation, check out this article:
http://www.zdnet.com/article/virtual-cpus-the-overprovisioning-penalty-of-vcpu-to-pcpu-ratios/
A very informative read Lee.  ;)

-saige-
I agree, very good article. So does Hyper-V have this symmetric multi-processing feature?
Yes, SMP is the concept of having at least 2 CPUs (or vCPUs).
Thanks for the advice here guys.