Hi Wizheng FLIP-6 [1] introduce a new implementation of master component in Flink cluster with name of `JobMaster.java`[2], you can find previous implementation in Flink-1.7 as `JobManager.scala` [3]. However, we would still call the master component as 'JobManager' though its implementation name has been changed. If you want to know more details, please read FLIP-6 and its JIRA issue FLINK-4319 [4].
[1] https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=65147077 [2] https://github.com/apache/flink/blob/release-1.10/flink-runtime/src/main/java/org/apache/flink/runtime/jobmaster/JobMaster.java [3] https://github.com/apache/flink/blob/release-1.7/flink-runtime/src/main/scala/org/apache/flink/runtime/jobmanager/JobManager.scala [4] https://issues.apache.org/jira/browse/FLINK-4319 Best Yun Tang ________________________________ From: Lu Weizheng <luweizhen...@hotmail.com> Sent: Friday, January 31, 2020 10:25 To: user@flink.apache.org <user@flink.apache.org> Subject: Difference between JobManager and JobMaster Hi all, Recently I am reading source code of Flink. There are both JobManager and JobMaster in flink-runtime project. And JobManagerRunner interface says it is a runner which executes a JobMaster. So how to distinguish the two concepts? Is JobMaster a subset of JobManager? Or JobMaster is a new version which is going to replace the function of JobManager? Or the two roles are different? Thank you! Weizheng
