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Creating VMware Virtual Servers CPU

I'm creating a new Server 2012 Windows server and have a question about the CPU setting.

I'm using VMware and need to create a server with 12 cores. When prompted for the CPU I'm given both a " Number of Virtual Sockets" and " Number of Cores per socket " .....

I don't totally understand these values and need a bit of help setting them.

Thanks ...

Joel

J0rtIT

I think that the best answer is this one:

In VMWare does not make a difference. It is purely based on how the CPU's are presented to the guest. Whether you choose dual sockets single core each, or single socket with dual-core, VMWare treats those as the same, you get 2 cores of CPU time.

The main reason this was added was for software licensing on the guests. In our case, our SQL server has a single processor license. If I want to allocate 4 cores and I use the default of 4 sockets single core each, then I am in violation of my SQL license, because that is 4 sockets. If I change that to a single processor with 4 cores, then I am legal again. I get the same performance in VMWare either way.

Microsoft has already announced that many of their new versions of the software will be on a per core license model, such as the new version of SQL Server.

Source:https://community.spiceworks.com/topic/189740-vmware-virtual-sockets-vs-cores-per-socket-which-give-better-performance

Also, there's an analytic answer about it here:

http://www.virtualizationsoftware.com/virtual-cores-virtual-sockets-vcpu-explained/

SOLUTION

Qlemo

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ASKER CERTIFIED SOLUTION

Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)

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Qlemo

This is true, many VMware Administrators, think adding lots of processors, will increase performance - wrong!
There is much truth in that. Imagine a machine running a single-threaded high-cpu process. With one processor, it can use 100% CPU. With two 50%, aso. No performance gain in regard to this single process. However, with a two+ CPU VM other processes can still run well if the high-CPU process goes full steam ahead.

Joel Brown

ASKER

I will be installing Sql 2016 standard on this server using the server/user cal licensing model. The software running on the server will require 12 cores ........

Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)

How many concurrent users will use the database ?

Does your host have dual processors ?

Qlemo

Sounds horribly oversized, but so be it. Just use sockets to get the best result - provided you can assign that much and they are recognized by the OS.

Joel Brown

ASKER

@ Andrew, At most we will have 50 concurrent users connected to the database .... The servers have 2 each of PROCESSOR, X5650, 2.66/6.4, 12MB, XWM, B1 .......

Joel

Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)

That's not many...I would refer to this document, to architect your SQL VM...

those are quite old HOST processors...check ESXi is supported and on HCL.

Architecting Microsoft SQL Server on VMware vSphere

Getting SQL Servers to perform well under a hypervisor - vSphere or Hyper-V - can be tricky and just throwing processors at it, sometimes may not be the best thing. Memory and Datastore IOPS is criticial!