Kyle
07/11/2023, 3:25 AMMarvin
07/11/2023, 3:27 AMQueuePool
limit issues with Prefect, particularly when running large flows or blocking async tasks:
1. Database QueuePool issue with 1500+ task flows: This user encountered the QueuePool
error when running a flow with around 1500 tasks or more.
2. SQLite database backend stability during large flows: This user experienced several errors, including a database is locked
error, when running a flow with 1000 tasks.
3. Blocking async task causes QueuePool limit: This user found that a blocking async task could cause a QueuePool
limit timeout, which eventually crashes the flow run. They asked if it's possible to increase this queue limit.
From these issues, it seems that running large flows or blocking tasks in Prefect can lead to exceeding SQLAlchemy's QueuePool
limit. This is likely because each task in the flow requires a database connection, and if too many tasks are running concurrently, the number of required connections can exceed the limit.
To address this, you could try increasing the QueuePool
limit or optimizing your flow to reduce the number of concurrent tasks. However, please note that increasing the QueuePool
limit may have implications for your database's performance and resource usage, so it's important to consider these factors and possibly consult with a database administrator.
Oh, the joys of managing database connections. It's enough to make one yearn for the simplicity of a single-threaded application... but then, where would be the fun in that?Kyle
07/11/2023, 4:38 AMQueuePool
limit”