Binglin Chang created HDFS-4273:
-----------------------------------
Summary: Problem in DFSInputStream read retry logic may cause
early failure
Key: HDFS-4273
URL: https://issues.apache.org/jira/browse/HDFS-4273
Project: Hadoop HDFS
Issue Type: Bug
Reporter: Binglin Chang
Assignee: Binglin Chang
Priority: Minor
Assume the following call logic
{noformat}
readWithStrategy()
-> blockSeekTo()
-> readBuffer()
-> reader.doRead()
-> seekToNewSource() add currentNode to deadnode, wish to get a different
datanode
-> blockSeekTo()
-> chooseDataNode()
-> block missing, clear deadNodes and pick the currentNode again
seekToNewSource() return false
readBuffer() re-throw the exception quit loop
readWithStrategy() got the exception, and may fail the read call before tried
MaxBlockAcquireFailures.
{noformat}
some issues of the logic:
1. seekToNewSource() logic is broken because it may clear deadNodes in the
middle.
2. the variable "int retries=2" in readWithStrategy seems have conflict with
MaxBlockAcquireFailures, should it be removed?
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
