Hello @Matteo,
welcome to this moderated Azure community forum.
The costs of an Azure Data Explorer is built up by several components:
- Engine instances
- Data management instances
- Storage and transactions
- Networking
- Azure Data Explorer markup
As you can see, there are two 'instances'.
The engine is the cluster you configure yourself. These are used for the (query) compute.
The Data management instances are the internal VMs, or internal load balancers (engine and data management) for ingestion and optimizing the storage:
The (Data management) service ... are automatically configured and managed based on the engine instance size.
So, you are (only) in control for the Compute engine instances.
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