Azure Price Calculator wierd pricing for VM Windows OS and SQL PAYG licenses

Question

I have tried various browsers, cleared cache, in private mode etc to no effect.
There is something going on with the Azure cost calculator, or the pricing policy/model is (perhaps deliberately) obscure...

https://azure.microsoft.com/en-gb/pricing/calculator/

I am trying to compare Reserved Instance and Software Subscription pricing for Windows server OS and SQL Standard licenses vs PAYG for the same products and it is proving to be all but impossible.

Examples of issues.

SQL and OS licenses are not consistently following the number of cores for the VM model = 2x CPU cores per "pack" for SQL and 8x CPU cores for Server OS.

Take Bs series on PAYG

B2ms = 2 CPU = £4.31 OS = £215.74 SQL Standard
B4ms = 4 CPU = £8.63 OS = £215.74 SQL Standard
B8ms = 8 CPU = £17.26 OS = £431.47 SQL Standard

The 2 CPU VM has the same price for SQL PAYG as a 4 CPU, but the 8 CPU model price is double the price ?
If SQL is licensed in packs of 2 and the PAYG price for 2 cores is x, then the price for 4 cores = x*2 and for 8 cores it should be x*4 etc.

Compare that with the pricing for Dsv2 Series

DS14-4 V2 = 4 CPU = £316 OS = £215.74 SQL Standard
DS14-8 V2 = 8 CPU = £316 OS = £431.47 SQL Standard
DS14 V2 = 16 CPU = £316.05 OS = £862.95 SQL Standard

The OS license comes in packs of 8 - I can understand that the 4 CPU model therefore costs the same to OS license as the 8 CPU model, but why is the 16 CPU model not 2x £316.05?! (2x packs of 8 core licenses to cover 16 cores)?
Why in D series is the SQL license cost consistently different between 4, 8 and 16 CPU models - compared with Bs series?

No less confusing: If Windows server OS is priced per core, regardless of the physical CPU model, why is the cost of a 4 CPU B series machine only £8.63 per month but £316 per month for 4 CPUs of a D series VM?!

Is this just a data issue with the calculator or something else?

Answer 1

Hello, @Sid Merrett !

A quick disclaimer before I try to answer your question: For questions about billing you'll want to reach out to billing directly as we're set up to answer questions of a more technical nature. You can do this by opening a billing ticket in the portal by going to Help + support > New support request > Billing and then completing the wizard.

Am I the only one seeing this?
I'm seeing the same prices you are from the Azure Pricing Calculator. No need to troubleshoot your browser or session. See more on exactly what I'm seeing below.

Making a comparison
Before getting into the pricing calculator, it may be helpful to use the pricing options guide when comparing the cost of several different VM SKUs or benefit price vs reserved price:

https://azure.microsoft.com/en-us/pricing/details/virtual-machines/sql-server-standard/

Example 1: The Bs Series
I went through the Bs-series with the following configuration:

Region: UK South
OS: Windows
Type: SQL Server
Tier: Standard
License: SQL Standard

Compute / OS (Windows) / Software (SQL Server)

B1ms (1 core ) : £12.73 / £2.16 / £215.74
B2ms (2 cores): £50.91 / £4.10 / £215.74
B4ms (4 cores): £101.94 / £8.63 / £215.74
B8ms (8 cores): £203.87 / £17.26 / £431.47
B12ms (12 cores): £305.27 / £25.89 / £647.21
B16ms (16 cores): £407.20 / £34.52 / £862.95
B20ms (20 cores): £509.14 / £43.15 / £1,078.68

At least for this example we see a relatively linear increase in OS cost that corresponds to the number of cores (at a little over £2 per core). For the software cost, it appears that there is a minimum cost up until 4 cores and then a linear increase of roughly £215.74 for every 4 cores added.

Example 2: DS SKUs
I went through the DS SKUs with the following configuration:

Region: UK South
OS: Windows
Type: SQL Server
Tier: Standard
License: SQL Standard

Compute / OS (Windows) / Software (SQL Server)

DS14-4 v2 (4 cores) : £1,010.73 / £316.05 / £215.74
DS14-8 v2 (8 cores) : £1,010.73 / £316.05 / £431.47
DS12 v2 (4 cores) : £252.95 / £78.74 / £215.74
DS13 v2 (8 cores) : £505.36 / £158.03 / £431.47
DS14 v2 (16 cores) : £1,010.73 / £316.05 / £862.95
DS15 v2 (20 cores) : £1,263.68 / £394.80 / £1,078.68

Here, having the DS14-4/8 v2 along side the DS12-15 v2 lineup helps make things clearer. You can see that both the DS14-4 v2 and DS14-8 v2 have the same OS cost as the DS14 v2 (£316.05) while the software cost matches the core count (£215.74 and £431.47). Looking at the DSv12-15 v2 you can see the same linear increase in OS and software cost.

Answer 2

Hi - thanks for the input.
Are you echoing my confusion or attempting to explain the anomalies though?

As far as I can see, your numbers confirm that there is a fundamentally indecipherable relationship between the cost of the OS and SQL licenses and the CPU count of a given VM model and series in Azure.

That is based on these principals: SQL Server is priced per 2 core "pack" and Windows Server OS in packs of 8 cores and and CPU performance is not relevant to license cost.

So the OS price varies wildly per-CPU based on VM series (i.e. performance). Why?
SQL Server is consistently priced per CPU core, except when there are only 2 cores. In which case, you pay for 4 core licenses. Why?

The key difficulty I am facing, is trying to put together real-world price comparisons between Reserved Instances, subscription (e.g. EA) SQL and OS licenses and PAYG equivalents.
Made difficult because Microsoft uses an unknown/unpublished pricing model on PAYG, for software licensing.

Answer 3

One other observation : Pricing of the virtual hardware (compute) is also strange in some series (of course it is the absolute discretion of the vendor, but why the inconsistency?)
For example, the DS14_V2 series 4, 8 and even 16 CPU machines are all priced the same for compute.
So you can have a 4, 8 or even 16 CPU core, 112Gb RAM VM for £1,010.73 per month compute on PAYG, in UK West.

?