I created an azure account for the purposes of utilizing the hbv3-series spot VMs given their excellent price/performance. I requested a 120 spot and hbv3 vcpu quota increase in each region with the SKU, requested smaller increases, all were denied. I reached out to support twice. First an increase in East US then UK South and both times I was told the increase was denied "due to very high rates of capacity demand". Both regions offer ~90% spot discounts with a 0-5% eviction rate, so there seems to be capacity. The SKU's spot cost is just ~0.4$/h, without any quota increases I can access on demand instances with higher prices than that. Is there support I can talk to that can actually offer help? What steps can I take to utilize this SKU with spot discounts?

Hello, @Tomás Silva ! Why was my quota increase request denied for the HBv3-series VM? The HBv3-series is only offered in a limited number of Azure regions which limits availability, especially for spot instances (which offers discounts for unused/idle VM hardware). It may be that 120 cores is more than the hardware that is available so you may want to try starting at 16 or 32 cores. From everything I can see, support was correct when they said that this is "due to very high rates of capacity demand". Another alternative would be to select a more common VM series if you are set on using Azure Spot instances.

Quota increase requests always denied

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kobulloc-MSFT 26,351 Reputation points Microsoft Employee

2024-06-20T22:29:25.74+00:00

Hello, @Tomás Silva !

Why was my quota increase request denied for the HBv3-series VM?

The HBv3-series is only offered in a limited number of Azure regions which limits availability, especially for spot instances (which offers discounts for unused/idle VM hardware). It may be that 120 cores is more than the hardware that is available so you may want to try starting at 16 or 32 cores.

From everything I can see, support was correct when they said that this is "due to very high rates of capacity demand". Another alternative would be to select a more common VM series if you are set on using Azure Spot instances.
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Tomás Silva 20 Reputation points

2024-06-21T00:23:49.8366667+00:00

Wouldn't the lack of availability be reflected on the spot discount? Both East US and UK South have ~90% discounts with 0-5% eviction rates. I currently use AWS and 90% discounts are rare to come by.

When I followed up with support asking what I could do to access the VM I was given the following response "I reviewed with our internal capacity team for an alternative option and the capacity team confirmed that for now there is no alternative option either with region or SKU.". This lead me to believe the issue was with my account being too new. Is it really the case that no region has any HBv3-series available?

If I am to take the support engineer's response at face value, then what options are there for me?

edit: I forgot to add. Unfortunately I don't have any use for 16 cores or 32 cores. Moreover, the price/hour is the same as 120 cores and with 16 cores or 32 cores I don't have a reason to switch from AWS to azure.

kobulloc-MSFT 26,351 Reputation points Microsoft Employee

2024-06-21T00:42:55.5533333+00:00

Hello, @Tomás Silva !

If I were to see both a 90% discount and a 5% eviction rate, I would come to the same conclusion. What makes this case unique is that the HBv3-series is only available in 8 or so out of all the dozens of Azure Regions. My guess is that this creates an edge case where only a couple VMs creates dramatically skewed numbers or that there are vCPU caps to promote use of available VM sizes (as a made up example, using Standard_HB120-32rs_v3 instead of Standard_HB120rs_v3).

I do know that these VMs are available outside of spot instances. I can try to get some more information regarding the logic of Azure Spot Instance availability if you are interested but it may take a while to get an answer and I suspect that the culprits in this scenario are either low overall VM count for this specific series or availability only in smaller sizes.

Tomás Silva 20 Reputation points

2024-06-21T01:32:32.43+00:00

I would imagine if there's a low overall VM count then the spot price and eviction rate should have big swings. Is there a way to get a ballpark on the amount of HB120rs v3 VMs available per region? For now I only need 1, but in the near future, if there is availability, I could use quite a bit more.

Is it possible there's other factors at play other than the lack of availability? Like the lack of payment history? Maybe being a low priority account?

I will contact support again and try a smaller quota increase, with the hope that will give way to larger increases in the future.

kobulloc-MSFT 26,351 Reputation points Microsoft Employee

2024-06-21T03:44:46.69+00:00

I'm cautiously optimistic about the smaller quota increase. I'll also follow up privately with some additional suggestions.
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