Microsoft Fabric Error:
HTTP 430
What does this error mean?
A Spark notebook, job, or pipeline in Fabric was rejected with HTTP 430 because the workspace has exceeded its allocated Compute Units (CUs) for Spark workloads.
Common causes
- 1Multiple Spark sessions running simultaneously in the workspace, exhausting the concurrent job limit for the capacity SKU
- 2A large-scale ETL operation consuming Compute Units beyond the SKU allocation
- 3Orphaned or stalled Spark sessions left running in the background, consuming CUs without doing work
- 4Capacity SKU is too small for the current Spark workload demands
- 5All capacity CUs consumed by other workloads in the same workspace
How to fix it
- 1Stop orphaned or stalled Spark sessions in the Fabric workspace (Workspace settings > Spark > Active sessions).
- 2Enable Autoscale Billing for Spark workloads — this offloads Spark jobs to dedicated serverless resources and eliminates CU consumption from capacity.
- 3Stagger Spark job schedules to avoid peak-time overlap where multiple heavy jobs run simultaneously.
- 4Upgrade the Fabric capacity SKU if your sustained Spark workload regularly exceeds the current CU allocation.
- 5Use Fabric capacity metrics (Capacity Metrics app) to identify which workloads are consuming the most CUs and optimize them.