Significant capacity consumption increase since July 7th without major changes

Hi ObungiNiels ,

Thank you for reaching out to the Microsoft Fabric Community Forum.

To address your questions, we can confirm that while there is no available documentation indicating a change in the cost model for shortcut-based access, we have observed some community feedback suggesting that using shortcuts and secured sources may lead to higher CU consumption. In your situation, enabling OneLake security on the Gold Lakehouse could be contributing to the increased usage, especially if the shortcut access now involves extra security enforcement layers or redirect logic. These actions may require additional backend compute or more thorough access checks, which might appear under the “redirect” category in the Capacity Metrics app.

Regarding your question about whether others have noticed similar behavior, while we can't speak for every tenant, there have been cases where customers using cross-workspace shortcuts or adding security features like ACLs or row-level access have reported differences in CU attribution. 

To proceed efficiently, we recommend reviewing whether there have been any recent changes to your workloads, such as newly scheduled pipelines or queries, which might have increased access frequency to the Platinum Lakehouses.

Please also confirm if shortcuts are being utilized across workspaces and whether row-level security or OneLake access controls are implemented, as this information could assist in further isolating the root cause. Enabling detailed Capacity Metrics logging, if not already active, is also advised to help identify specific users or operations affecting consumption patterns.

For further clarity, Microsoft’s official documentation on OneLake consumption explains how CU usage is attributed, especially when using shortcuts and security features. It confirms that:

• CU consumption is attributed to the workspace accessing the shortcut, not the source.
• Security features like RLS can increase CU usage depending on the number of rows secured.

If the issue persists without any workload changes, we recommend submitting a formal support ticket with Microsoft to initiate a backend review by the engineering team.

Please keep us informed of any further insights or updates on your end. I hope my suggestions give you good ideas, if you need any further assistance, feel free to reach out.

Thank you.