[
https://issues.apache.org/jira/browse/HDFS-12416?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Suhan Mao updated HDFS-12416:
-----------------------------
Status: Patch Available (was: Open)
Patch submitted.
The patch will check whether the stringbuilder is null before it is used.
> BlockPlacementPolicyDefault will cause NN shutdown if log level is changed
> --------------------------------------------------------------------------
>
> Key: HDFS-12416
> URL: https://issues.apache.org/jira/browse/HDFS-12416
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: block placement
> Affects Versions: 3.0.0-alpha3, 2.7.4
> Reporter: Suhan Mao
> Attachments: HDFS-12416.001.patch, HDFS-12416.patch
>
> Original Estimate: 5h
> Remaining Estimate: 5h
>
> In BlockPlacementPolicyDefault.chooseRandom method.
> The code are in below structure:
> {code:java}
> StringBuilder builder = null;
> if (LOG.isDebugEnabled()) {
> builder = debugLoggingBuilder.get();
> builder.setLength(0);
> builder.append("[");
> }
> while(numOfReplicas > 0){
> .............
> chooseDataNode(scope, excludedNodes)
> .............
> if (LOG.isDebugEnabled()) {
> builder.append("\nNode ").append(NodeBase.getPath(chosenNode))
> .append(" [");
> }
> }
> {code}
> There's a possibility that the loglevel is INFO before entering while loop,
> but the loglevel is changed to DEBUG inside the loop through web UI.
> In that case, builder is not initialized in the beginning and
> NullPointerException will throw and this will cause NN exiting.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]