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julezatmortonbu
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NUMA Nodes, SQL Server and confusion

So for whatever reason I'm currently seeing one of our SQL VMs use 2 NUMA nodes through ESXTOP.

I've been reading the following blog post.

Does corespersocket Affect Performance? | VMware vSphere Blog - VMware Blogs

We have hosts that are dual socket, 6 core with hyperthreading (24 logical procs).
Our primary SQL VM is currently 2 virtual sockets and 6 virtual cores, 12 logical procs total, which should equate still into a single NUMA node, unless the way it's configured caused it to span (my guess).

At the time the we didn't realize that that you couldn't hot add cores and could only do sockets, so later on we added the socket for 12 vcpus.

Anyway, I was sold after reading the blog that I wanted to go with 12 vcores and be done with it.
But then I started to read the comments <never a good idea Smiley Wink> and then became confused on how the physical NUMA vs virtual NUMA actually affects performance.
Should I do  1 core x 12 sockets or should I do 12 core and 1 socket?

The memory allocated is definitely within the spec of a single physical NUMA node for sure.

So I guess I'm asking, you have a SQL server like that that houses mostly our Dynamics AX database and a few others, hence the need for the horsepower.  Which route would you go with this?
And is there always a performance hit when you add in more vcpu than a single physical socket has?

I think I've just confused myself along the way is all.

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