[CAMEL-21435] Commons-pool2: When Camel Netty configured with producerPoolMaxTotal=1 and retry, the application hangs

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Information Provided
• Fix Version/s: 4.9.0
• Component/s: camel-netty
• Estimated Complexity: Unknown
• Assignee: Claus Ibsen
• Reporter: Dmitrii Kriukov
• Created: 11/Nov/24 17:35
• Updated: 13/Nov/24 09:32
• Resolved: 13/Nov/24 09:20

Description

Retry on the onException() clause seems to be impossible for producerPoolMaxTotal=1 (leads to call of GenericObjectPoolConfig.setMaxTotal())
This causes infinite hanging in case of network IO exceptions.
Netty attempts to utilize a new connection when the old one is still unreleased.
It boils down to method org.apache.commons.pool2.impl.GenericObjectPool::borrowObject(Duration borrowMaxWaitDuration) throws Exception {}
When producerPoolBlockWhenExhausted = true (the default value), the application hangs.
When producerPoolBlockWhenExhausted = false, I get an exception 
2024-11-11 13:41:44 ERROR [com.opt.obp.ser.ada.cam.Logger] (Camel Thread #2 - NettyClientTCPWorker) <> Exception occurred: java.util.NoSuchElementException: Pool exhausted 
So, either way it's impossible to serve