Concurrent Workflow Jobs

[holychs]

Hi Community, 

I am trying to run a Databricks workflow job using run_job_task under a for_loop. I have set the concurrent jobs as 2. 

I can see 2 iteration jobs getting triggered successfully. But both fail with an error:

"ConnectException: Connection refused (Connection refused)

Error while obtaining a new communication channel"

Contradictory to the fact that same job gets completed successfully with concurrency as 1. 

Cluster Configuration: Driver: Standard_DS5_v2 · Workers: Standard_DS5_v2 · 4-8 workers

[TakuyaOmi]

Hi, @holychs 

Did you encounter any error messages related to an OOM (Out of Memory) error?
It’s possible that the driver node of the cluster doesn’t have sufficient resources (CPU, memory) to handle multiple concurrent jobs.