Will VMware use all cores in processor or can I limit them?

I am trying to figure out what the options are to configure processor and cores on a VM.  I am licensed for vCenter and vSphere 5.5 (1 instance/1 cpu) and setting up a new server with 1 processor/6 core.

Can I setup a virtual server to run on 4 cores or will it want to use all 6 cores?  The reason I want to know is because I will be licensing SQL 2012 based on cores and not CAL's.  If I can run the SQL server on 4 cores instead of 6 I will save $3500 on the license.
schwientekdIT DirectorAsked:
Who is Participating?
 
AbhilashBloggerCommented:
Yup you can setup VM to use 4 cores. When you setup VM to use 4 cores it will only use four cores.
But you will not know which 4 cores of 6 cores will be used.
0
 
schwientekdIT DirectorAuthor Commented:
Is there a downside to doing this and not knowing which cores are being used?
0
 
AbhilashBloggerCommented:
As far as i understand from licensing, you do not license the host physical CPU. Even if you have a 4 Core CPU and hyper-threading enabled, and you have two VM's running SQL you will have to buy 8 licenses.

So what i feel is that you will be licensing for virtual cores in your VM. So even though your host has 6 cores, you will assign 4 cores to VM and then license it.

I don't see any problem with it. Independant of which core on physical CPU is used for VM. The license will work fine.

Hope i did not confuse you.

Let me know if you got it. Or i'll try putting it in a better way.
0
Improve Your Query Performance Tuning

In this FREE six-day email course, you'll learn from Janis Griffin, Database Performance Evangelist. She'll teach 12 steps that you can use to optimize your queries as much as possible and see measurable results in your work. Get started today!

 
schwientekdIT DirectorAuthor Commented:
That makes sense to me and how I thought it should work.  I was just looking for a perspective from someone else.  Thank you very much!
0
 
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Just be careful, you do not over allocate vCPUs, in a VM.

In can have the non-desired effect sometimes, of reducing performance.

Few VMs require more than 2 vCPU, start at 1 vCPU and add. (you can always remove easily!).
0
 
schwientekdIT DirectorAuthor Commented:
That is good advice, much appreciated.
0
 
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
No problems.
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.