Question

A nightly pipeline uses a single Copy activity to move 500 GB from an on-premises SQL Server (via an on-premises data gateway) into a Fabric Lakehouse Delta table. The copy takes over 6 hours, and you must reduce the duration. When you inspect the Copy activity's monitoring details, you see the Data Integration Units (DIU) used are automatically capped and throughput plateaus far below the destination's capability. What is the MOST likely bottleneck and the appropriate first action?

Accepted Answer

The on-premises data gateway is the bottleneck; scale out by adding gateway nodes and increasing the gateway's concurrent job/CPU limits

Answer

The destination Lakehouse is throttled; enable V-Order and Z-Order on the target Delta table before the copy runs

Answer

Insufficient DIUs; manually raise the DIU setting to 256 on the Copy activity to remove the automatic cap

Answer

The source query lacks statistics; run UPDATE STATISTICS on the SQL Server table to speed up the extract