Based on your situation, there are several approaches you can take to resolve the timeout issue: 1. Increase Database Timeout (Recommended First Step) Set the

PREFECT_API_DATABASE_TIMEOUT

environment variable to a higher value (in seconds) before starting your Prefect server:

bash
   export PREFECT_API_DATABASE_TIMEOUT=300  # 5 minutes

2. Database-Level Solution If you're using RDS PostgreSQL, you can also adjust the statement timeout at the database level:

sql
   ALTER DATABASE your_prefect_db SET statement_timeout = '300000';  -- 300 seconds (5 minutes)

Or for the current session only:

sql
   SET statement_timeout = '300000';

3. Manual Deletion If the UI deletion continues to fail, you can delete the flow run directly from the database. However, this should be done with extreme caution as it might leave orphaned data. Here's the general approach:

sql
   -- First, identify the flow run
   SELECT * FROM flow_run WHERE id = 'your-flow-run-id';
   
   -- Then delete it (be very careful with this!)
   DELETE FROM flow_run WHERE id = 'your-flow-run-id';

Important Considerations: - Before making any direct database changes, always backup your database - If you're running in a containerized environment, make sure to set the environment variable in your container configuration - Consider investigating why this particular deletion is timing out - it might indicate a larger issue with database performance or size - If you're experiencing frequent timeouts, you might want to implement a regular cleanup strategy to prevent the database from growing too large The safest approach is to start with increasing the

PREFECT_API_DATABASE_TIMEOUT

environment variable. If that doesn't resolve the issue, you may want to investigate the size of your database and consider implementing a retention policy to automatically clean up old flow runs. For more information about self-hosted Prefect server configuration, you can refer to the official documentation.

@Marvin what is the default database timeout, when not specified explicitly?

The default database timeout in Prefect is 10 seconds when

PREFECT_API_DATABASE_TIMEOUT

is not explicitly set. This is quite conservative and might be insufficient for larger databases or operations involving many records, which explains why you're experiencing timeout issues when trying to delete flow runs. Given this relatively short default timeout, it's not uncommon to need to increase this value in production environments, especially when working with self-hosted instances that may have accumulated significant amounts of data.