Fabric Capacity Planning - Paying by the Hour?

[jon_clemens]

If this is not the correct forum for this question, please direct me to the correct forum.

I see on the MS Fabric pricing info, that they list a price per hour per capacity unit.  Is this just informational, or is there a way to confiugre a capacity so you are not paying for a full 24 hours in a day, if you don't need that.

If so, how does this impact the way different capacity utilization is spread?  Does the utilization that spreads over 24 hours still spread over the 24 hours of the day, or over the 24 hours you are paying for. 

We have a consultant that is suggesting that we subscribe to higher CU F-SKU, but only use for 8 to 10 hours per day, therefore paying less per month.  I am wondering if this is older "Synapse" thinking, and not as applicable to Fabric Capacities - given the logic of spreading out utilization over time, depending on the scenario.

Thx.

[Joe_Barry]

Hi @jon_clemens 

From what I have seen, there are quite lage discounts for a reserved Capacity. With the Pay as you go, you can have a maximum of 14 hours a day in a 30 day month with pay as you go to reach the €179 the reseravtion costs per month. So anything under 14 hours is cheaper.

Joe

[jon_clemens]

Thanks.  I am looking for some guidance as well on the exact configuration that would enable the concept of paying only for 10 - 12 hours a day.  Do you have to pause the capacity every day for the other hours?  How does this affect the way the spreading of usage calculation to occur?

[Anonymous]

Your ideas is so great @Joe_Barry 

Hi, @jon_clemens 

Existing Power BI Premium customers can use Fabric capacities because they behave similarly to Power BI Premium capacities. However, because Fabric capacity is pay-as-you-go, it's more costly, allowing for dynamic scaling and pausing without a usage commitment.

You can see the predicted price from the calculator on the official website of the subscription:

The price of CU is different in different regions, and it is also affected. For example, each CU in the figure is about $0.18.

In addition, you can also read these articles below, and I think you can also learn about the burst and smoothing features.

Fabric Capacities – Everything you need to know about what’s new and what’s coming | Microsoft Fabri...

When we only have 64 CUs, the burst can use 256 CUs to complete the job in 15 seconds, instead of running the job on 64 CUs and completing in 60 seconds.

Save costs with Microsoft Fabric Capacity reservations - Microsoft Cost Management | Microsoft Learn

You also need to understand how cu consumption is calculated in Fabric:

Plan your capacity size - Microsoft Fabric | Microsoft Learn

Your advisor recommends subscribing to a higher CU F-SKU but only using it for 8-10 hours per day, which is valid.
Before you purchase a CU F-SKU, you will need to actively monitor your daily usage using some metrics, reports, or other methods, using the Rest API to ensure that your consumption meets your actual expectations.
In addition, you can communicate your ideas with Microsoft sales when purchasing capacity to determine the right scenario.

Best Regards

Jianpeng Li

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[jon_clemens]

Thank you for the response.  I have reviewed the links you shared, which I had read previously.  I still don't think I have a direct answer to my direct qustion.  My question is:  How is the smoothing calculated if you pause/suspend a capacity every day, so you only pay for 8 hours a day (as an example.).  Is the smoothing still calculated over 24 hours of actual time?  24 hours of when the capacity is running - so over 3 days in my example?  the 8 hours the capacity is running within the 24 hours of actual time?

To spell out my example even more.  Let's say that I have a process where I have my capacity running only from 8 AM to 4 PM every day - so 8 hours.  Let's say I have a background process that will smooth over 24 hours, that takes 240 CU usage.  Which of the following will be how that usage is actually smoothed:

	Day 1	Day 2	Day 3
spread over 24 clock hours	10 CU usage per hour
spread over 24 hours of capacity running	10 CU usage per hour for 8 hours	10 CU usage per hour for 8 hours	10 CU usage per hour for 8 hours
spread over the 8 hours capacity is running in the 24 hours	30 CU usage per hour for 8 hours

[Anonymous]

Hi, @jon_clemens 

Thank you very much for your reply. The description I found in the documentation is: The amount of capacity provided by the given SKU per 30-second period is shown along with the breakdown of interactive and background operations.

In this section, an example of a price calculation:

We can learn more about smoothing:

You can try to understand: Throttle triggers and throttle stages

All of the above documents you can find from the links below:

Data warehouse billing and utilization reporting - Microsoft Fabric | Microsoft Learn

Smoothing and throttling in Fabric Data Warehousing - Microsoft Fabric | Microsoft Learn

Understand your Fabric capacity throttling - Microsoft Fabric | Microsoft Learn

Burstable capacity - Microsoft Fabric | Microsoft Learn

I hope the above can help you again. If you have detailed questions, you can consult Microsoft's corresponding sales, and they will answer this knowledge for you in detail.

Best Regards

Jianpeng Li

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.