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AllCovered-7028 asked TravisCragg-MSFT commented

physical cores vs vcpus, do we have 8 physical cores or 8vcpus?

Hello, i apologize in advance if this has been asked millions of times before but just hoping to get a clear response from MS Azure directly if possible. We currently have this vm instance: "Standard DS14-8_v2 (8 vcpus, 112 GiB memory)". We want to know if what is stated here: https://docs.microsoft.com/en-us/azure/virtual-machines/acu correlates to my question. The table on the link says that the "DS1_v2 - DS15_v2" sku family maps to "vcpu:core" 1:1 ratio. I just need official confirmation that our vm instance: "Standard DS14-8_v2 (8 vcpus, 112 GiB memory)" means that we have 8 physical cores or 8 vcpus?

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TravisCragg-MSFT answered TravisCragg-MSFT commented

Can you clarify a bit more on why exactly you need to know this?

This does have core mapping, the big difference here is that the DS_v2 SKUs do not have hyperthreading.

These are NOT physical cores, they are virtual cores as defined on the host.

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Ah, thanks for the clarification!

The reason we(our internal tableau devs) are asking this is due to licensing from tableau. Tableau is telling our internal tableau devs that they essentially do not care if the cores are virtual or physical, the license price will still be the same for either 8 physical cores or 8 virtual cores. Tableau also recommended that we reach out to Azure to check if they offered physical cores since they think physical cores would be a significant performance increase over virtual cores(i call bs on this and they also want to charge $72k/year extra for 16 cores!). But now that you clarified that the DS_v2 skus do not have hyperthreading and do have core mapping, i got some ammo for our stubborn internal tableau devs that think we need physical cores (and more of them) when we really do not. This, and some perfinsights logs.

Thanks again!

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I would do some testing on a few different series to see what gives you the most bang for your buck.

It can be a pain, but changing the size of an existing VM is easy. Spin up a VM &configure, run the perf test. stop the VM, resize to the next size you want to try, run the test again.

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