[KAFKA-7380] Global thread restore blocks KafkaStreams#start()

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: streams
• Assignee: Richard Yu
• Reporter: Matthias J. Sax
• Created: 06/Sep/18 00:24
• Updated: 28/Jul/20 03:58

Description

KafkaStreams#start() is documented to be non-blocking and should return immediately. However, if global stores are used, `start()` blocks until all global stores are restored.

We should change this and start all threads at the same time while all StreamThread would to go `wait()` state on startup immediately, and only resume after global thread restore finishes and `wakeup()` all StreamThreads. 

Issue Links

• is related to: KAFKA-7198 Enhance KafkaStreams start method javadoc
• relates to: KAFKA-10317 Global thread should honor shutdown signal during bootstrapping
• links to: GitHub Pull Request #5879