Hi Stephan,
Thank you for detail explaination. As you said, my opition is to keep task
still running druing jobmanager failover, even though sending update status
failed.
For the first reason you mentioned, if i understand correctly, the key issue is
status out of sync between taskmanager and jobmanager. For example, when the
jobmanager failover, the task is at CREATED status . When the task status
transition to RUNNING, the updateStatus message can not be received because of
jobmanager failover, then the taskmanager will retry sending the message to
jobmanager until success. When the jobmanager recovers, the previous status of
task is still CREATED in jobmanager view, and the task status maybe actually
transition to FINISHED in taskmanager view. The key problem is that when the
jobmanager received the FINISHED earlier than the RUNNING message, it will
reject the FINISHED message. If the task maintain a queue for sending message
during jobmanager failover in order to confirm that the messages will be
received in sequence at jobmanager when recover, that means the RUNNING status
message must be arrived before FINISHED status message, are there any problems?
For the second reason you mentioned, i am not very clear of the machenism of
filtering the critical message by leaderSessionID, would you extend it in
detail?
I am trying to improve process of jobmanager and taskmanager failover, thank
you for your help!
Zhijiang Wang
