Jun Gong commented on YARN-4497:

In *RMStateStore#notifyStoreOperationFailedInternal*, RMStateStore might skip 
store errors, so RMStateStore might fail to store attempt2 for some 
reasons(e.g. network error), but the app could continue running, and starts a 
new attempt attempt3, then RMStateStore stores attempt3 successfully(suppose 
network is OK now).

> RM might fail to restart when recovering apps whose attempts are missing
> ------------------------------------------------------------------------
>                 Key: YARN-4497
>                 URL: https://issues.apache.org/jira/browse/YARN-4497
>             Project: Hadoop YARN
>          Issue Type: Bug
>            Reporter: Jun Gong
>            Assignee: Jun Gong
> Find following problem when discussing in YARN-3480.
> If RM fails to store some attempts in RMStateStore, there will be missing 
> attempts in RMStateStore, for the case storing attempt1, attempt2 and 
> attempt3, RM successfully stored attempt1 and attempt3, but failed to store 
> attempt2. When RM restarts, in *RMAppImpl#recover*, we recover attempts one 
> by one, for this case, we will recover attmept1, then attempt2. When 
> recovering attempt2, we call  
> *((RMAppAttemptImpl)this.currentAttempt).recover(state)*, it will first find 
> its ApplicationAttemptStateData, but it could not find it, an error will come 
> at *assert attemptState != null*(*RMAppAttemptImpl#recover*, line 880).

This message was sent by Atlassian JIRA

Reply via email to