【Retention】Lookup of the expired workflow instance database timeout

I use sqlserver to store the workflow instances and currently have a timer that fires 5 child workflows every second, producing over 300,000 workflow instances in about 3 days. The background setup executes every 1 hours to clean up the workflow that was completed seven days ago, but on the third day, a timeout exception will be raised, which will eventually cause the application to crash.

The current version is 3.5.1.

Below is a screenshot of the system event log: