[
https://issues.apache.org/jira/browse/HADOOP-15121?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16333014#comment-16333014
]
Hanisha Koneru commented on HADOOP-15121:
-----------------------------------------
We can check that the {{metricsProxy#delegate}} object is not the same as the
current {{DecayRpcScheduler}} object before setting it again. We can do this in
\{{MetricsProxy#getInstance()}}.
{code:java}
if (mp == null) {
// We must create one
mp = new MetricsProxy(namespace, numLevels, drs);
INSTANCES.put(namespace, mp);
} else {
if (mp.delegate.get() != drs) {
mp.setDelegate(drs);
}
}{code}
> Encounter NullPointerException when using DecayRpcScheduler
> -----------------------------------------------------------
>
> Key: HADOOP-15121
> URL: https://issues.apache.org/jira/browse/HADOOP-15121
> Project: Hadoop Common
> Issue Type: Bug
> Affects Versions: 2.8.2
> Reporter: Tao Jie
> Assignee: Tao Jie
> Priority: Major
> Attachments: HADOOP-15121.001.patch, HADOOP-15121.002.patch,
> HADOOP-15121.003.patch, HADOOP-15121.004.patch, HADOOP-15121.005.patch,
> HADOOP-15121.006.patch, HADOOP-15121.007.patch
>
>
> I set ipc.8020.scheduler.impl to org.apache.hadoop.ipc.DecayRpcScheduler, but
> got excetion in namenode:
> {code}
> 2017-12-15 15:26:34,662 ERROR impl.MetricsSourceAdapter
> (MetricsSourceAdapter.java:getMetrics(202)) - Error getting metrics from
> source DecayRpcSchedulerMetrics2.ipc.8020
> java.lang.NullPointerException
> at
> org.apache.hadoop.ipc.DecayRpcScheduler$MetricsProxy.getMetrics(DecayRpcScheduler.java:781)
> at
> org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.getMetrics(MetricsSourceAdapter.java:199)
> at
> org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.updateJmxCache(MetricsSourceAdapter.java:182)
> at
> org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.getMBeanInfo(MetricsSourceAdapter.java:155)
> at
> com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getNewMBeanClassName(DefaultMBeanServerInterceptor.java:333)
> at
> com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:319)
> at
> com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:522)
> at org.apache.hadoop.metrics2.util.MBeans.register(MBeans.java:66)
> at
> org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.startMBeans(MetricsSourceAdapter.java:222)
> at
> org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.start(MetricsSourceAdapter.java:100)
> at
> org.apache.hadoop.metrics2.impl.MetricsSystemImpl.registerSource(MetricsSystemImpl.java:268)
> at
> org.apache.hadoop.metrics2.impl.MetricsSystemImpl.register(MetricsSystemImpl.java:233)
> at
> org.apache.hadoop.ipc.DecayRpcScheduler$MetricsProxy.registerMetrics2Source(DecayRpcScheduler.java:709)
> at
> org.apache.hadoop.ipc.DecayRpcScheduler$MetricsProxy.<init>(DecayRpcScheduler.java:685)
> at
> org.apache.hadoop.ipc.DecayRpcScheduler$MetricsProxy.getInstance(DecayRpcScheduler.java:693)
> at
> org.apache.hadoop.ipc.DecayRpcScheduler.<init>(DecayRpcScheduler.java:236)
> at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
> Method)
> at
> sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
> at
> sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
> at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
> at
> org.apache.hadoop.ipc.CallQueueManager.createScheduler(CallQueueManager.java:102)
> at
> org.apache.hadoop.ipc.CallQueueManager.<init>(CallQueueManager.java:76)
> at org.apache.hadoop.ipc.Server.<init>(Server.java:2612)
> at org.apache.hadoop.ipc.RPC$Server.<init>(RPC.java:958)
> at
> org.apache.hadoop.ipc.ProtobufRpcEngine$Server.<init>(ProtobufRpcEngine.java:374)
> at
> org.apache.hadoop.ipc.ProtobufRpcEngine.getServer(ProtobufRpcEngine.java:349)
> at org.apache.hadoop.ipc.RPC$Builder.build(RPC.java:800)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.<init>(NameNodeRpcServer.java:415)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNode.createRpcServer(NameNode.java:755)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:697)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:905)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:884)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1610)
> at
> org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1678)
> {code}
> It seems that {{metricsProxy}} in DecayRpcScheduler should initiate its
> {{delegate}} field in its Initialization method
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: common-issues-h...@hadoop.apache.org
