OneLake compute and storage consumption

OneLake usage is defined by data stored and the number of transactions. This page contains information on how all of OneLake usage is billed and reported.

Storage

OneLake storage is billed at a pay-as-you-go rate per GB of data used and doesn't consume Fabric Capacity Units (CUs). Fabric items like lakehouses and warehouses consume OneLake storage. Data stored in OneLake for Power BI import semantic models is included in the price of your Power BI licensing. For Mirroring storage, data up to a certain limit is free based on the purchased compute capacity SKU you provision. For more information about pricing, see Fabric pricing.

You can visualize your OneLake storage usage in the Fabric Capacity Metrics app in the Storage tab. Also note that soft-deleted data is billed at the same rate as active data. For more information about monitoring usage, see the Metrics app Storage page. To understand OneLake consumption more, see the OneLake Capacity Consumption page

Transactions

Requests to OneLake, such as reading or writing data, consume Fabric Capacity Units. The rates in this page define how much capacity units are consumed for a given type of operation.

Operation types

OneLake uses the same mappings as Azure Data Lake Storage (ADLS) to classify the operation to the category.

This table defines CU consumption when OneLake data is accessed using applications that redirect certain requests. Redirection is an implementation that reduces consumption of OneLake compute.

Operation in Metrics App Description Operation Unit of Measure Consumption rate
OneLake Read via Redirect OneLake Read via Redirect Every 4 MB, per 10,000* 104 CU seconds
OneLake Write via Redirect OneLake Write via Redirect Every 4 MB, per 10,000* 1626 CU seconds
OneLake Iterative Read via Redirect OneLake Iterative Read via Redirect Per 10,000 1626 CU seconds
OneLake Iterative Write via Redirect OneLake Iterative Write via Redirect Per 100 1300 CU seconds
OneLake Other Operations via Redirect OneLake Other Operations via Redirect Per 10,000 104 CU seconds

This table defines CU consumption when OneLake data is accessed using applications that proxy requests.

Operation in Metrics App Description Operation Unit of Measure Consumption rate
OneLake Read via Proxy OneLake Read via Proxy Every 4 MB, per 10,000* 306 CU seconds
OneLake Write via Proxy OneLake Write via Proxy Every 4 MB, per 10,000* 2650 CU seconds
OneLake Iterative Read via Proxy OneLake Iterative Read via Proxy Per 10,000 4798 CU seconds
OneLake Iterative Write via Proxy OneLake Iterative Write via Proxy Per 100 2117.95 CU seconds
OneLake Other Operations OneLake Other Operations Per 10,000 306 CU seconds

*For files > 4 MB in size, OneLake counts a transaction for every 4 MB block of data read or written. For files < 4 MB, a full transaction is counted. For example, if you do 10,000 read operations via Redirect and each file read is 16 MB in size, your capacity consumption is 40,000 transactions or 416 CU seconds.

Shortcuts

When you access data via OneLake shortcuts, the transaction usage counts against the capacity tied to the workspace where the shortcut is created. The capacity where the data is ultimately stored (that the shortcut points to) is billed for the data stored.

When you access data via a shortcut to a source external to OneLake, such as to ADLS Gen2, OneLake does not count the CU usage for that external request. The transactions would be charged directly to you by the external service such as ADLS Gen2.

Paused Capacity

When a capacity is paused, the data stored is continued to be billed using the pay-as-you-go rate per GB. All transactions to that capacity are rejected when it is paused, so no Fabric CUs are consumed due to OneLake transactions. To access your data or delete a Fabric item, the capacity needs to be resumed. You can delete the workspace while a capacity is paused.

The consumption of the data via shortcuts is always counted against the consumer’s capacity, so the capacity where the data is stored can be paused without disrupting downstream consumers in other capacities. See an example on the OneLake Capacity Consumption page

Disaster recovery

OneLake usage when disaster recovery is enabled is also defined by the amount of data stored and the number of transactions.

Disaster recovery storage

When disaster recovery is enabled, the data in OneLake gets geo-replicated. Thus, the storage is billed as Business Continuity and Disaster Recovery (BCDR) Storage. For more information about pricing, see Fabric pricing.

Disaster recovery transactions

Important

Currently, OneLake BCDR transactions via Redirect are consuming Fabric CUs at the rate of non-BCDR transactions. The CU consumption for OneLake BCDR write operations is higher than non-BCDR. This is a temporary situation. Kindly check the Known Issues for updates on when the issue will be corrected.

When disaster recovery is enabled for a given capacity, write operations consume higher capacity units.

Disaster recovery operation types

This table defines CU consumption when disaster recovery is enabled and OneLake data is accessed using applications that redirect certain requests. Redirection is an implementation that reduces consumption of OneLake compute.

Operation Description Operation Unit of Measure Capacity Units
OneLake BCDR Read via Redirect OneLake BCDR Read via Redirect Every 4 MB, per 10,000 104 CU seconds
OneLake BCDR Write via Redirect OneLake BCDR Write via Redirect Every 4 MB, per 10,000 3056 CU seconds
OneLake BCDR Iterative Read via Redirect OneLake BCDR Iterative Read via Redirect Per 10,000 1626 CU seconds
OneLake BCDR Iterative Write via Redirect OneLake BCDR Iterative Write via Redirect Per 100 2730 CU seconds
OneLake BCDR Other Operations Via Redirect OneLake BCDR Other Operations Via Redirect Per 10,000 104 CU seconds

This table defines CU consumption when disaster recovery is enabled and OneLake data is accessed using applications that proxy requests.

Operation Description Operation Unit of Measure Capacity Units
OneLake BCDR Read via Proxy OneLake BCDR Read via Proxy Every 4 MB, per 10,000 306 CU seconds
OneLake BCDR Write via Proxy OneLake BCDR Write via Proxy Every 4 MB, per 10,000 3870 CU seconds
OneLake BCDR Iterative Read via Proxy OneLake BCDR Iterative Read via Proxy Per 10,000 4798 CU seconds
OneLake BCDR Iterative Write via Proxy OneLake BCDR Iterative Write via Proxy Per 100 3415.5 CU seconds
OneLake BCDR Other Operations OneLake BCDR Other Operations Per 10,000 306 CU seconds

Changes to Microsoft Fabric workload consumption rate

Consumption rates are subject to change at any time. Microsoft will use reasonable efforts to provide notice via email or through in-product notification. Changes shall be effective on the date stated in Microsoft's Release Notes or Microsoft Fabric Blog. If any change to a Microsoft Fabric Workload Consumption Rate materially increases the Capacity Units (CU) required to use a particular workload, customers may use the cancellation options available for the chosen payment method.