[ 
https://issues.apache.org/jira/browse/HDFS-16836?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17631431#comment-17631431
 ] 

Xiaoqiao He commented on HDFS-16836:
------------------------------------

[~Lei Yang] Great catch and thanks for your report.
{quote}doCheckpoint() failed.
{quote}
Do you mean doCheckpoint failed but not throw exception or error, then 
needRollbackImage set back to false? Would you mind try to submit PR to fix it 
following this guide,  
https://cwiki.apache.org/confluence/display/HADOOP/How+To+Contribute Thanks.

> StandbyCheckpointer can still trigger rollback fs image after RU is finalized
> -----------------------------------------------------------------------------
>
>                 Key: HDFS-16836
>                 URL: https://issues.apache.org/jira/browse/HDFS-16836
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: hdfs
>            Reporter: Lei Yang
>            Priority: Major
>
> StandbyCheckpointer trigger rollback fsimage when RU is started.
> When ru is started, a flag (needRollbackImage) was set to true during edit 
> log replay.
> And it only gets reset to false when doCheckpoint() succeeded.
> Think about following scenario:
>  # Start RU, needRollbackImage is set to true.
>  # doCheckpoint() failed.
>  # RU is finalized.
>  # namesystem.getFSImage().hasRollbackFSImage() is always false since 
> rollback image cannot be generated once RU is over.
>  # needRollbackImage was never set to false.
>  # Checkpoints threshold(1m txns) and period(1hr) are not honored.
> {code:java}
> StandbyCheckpointer:
> void doWork() {
>  ....
>   doCheckpoint();
>   // reset needRollbackCheckpoint to false only when we finish a ckpt
>   // for rollback image
>   if (needRollbackCheckpoint
>       && namesystem.getFSImage().hasRollbackFSImage()) {
>     namesystem.setCreatedRollbackImages(true);
>     namesystem.setNeedRollbackFsImage(false);
>   }
>   lastCheckpointTime = now;
> } {code}



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org

Reply via email to