ZanderXu

HDFS-16728. RBF throw IndexOutOfBoundsException with disableNameServices

5

### Description of PR RBF will throw an IndexOutOfBoundsException when the namespace is disabled. Suppose we have a mount point /a/b -> ns0 -> /a/b and disabled the ns0. RBF...

HDFS-16724. RBF should support get the information about ancestor mount points

4

### Description of PR Suppose RBF cluster have 2 nameservices and to mount point as below: - /user/ns1 -> ns1 -> /user/ns1 - /usre/ns2 -> ns2 -> /user/ns2 Suppose we...

HDFS-16705. RBF: Support healthMonitor timeout configurable and cache NN and client proxy in NamenodeHeartbeatService

20

### Description of PR When I read NamenodeHeartbeatService.class of RBF, I feel that there are somethings we can do for NamenodeHeartbeatService.class. - Cache NameNode Protocol and Client Protocol to avoid...

HDFS-16703. Enable RPC Timeout for some protocols of NameNode.

26

### Description of PR When I read some code about protocol, I found that only ClientNamenodeProtocolPB proxy with RPC timeout, other protocolPB proxy without RPC timeout, such as RefreshAuthorizationPolicyProtocolPB, RefreshUserMappingsProtocolPB,...

HDFS-16695. Improve code with Lambda in org.apache.hadoop.hdfs.servernamenode package

9

### Description of PR Improve Code with Lambda in org.apahce.hadoop.hdfs.server.namenode package. For example: Current logic: ``` public ListenableFuture getJournaledEdits( long fromTxnId, int maxTransactions) { return parallelExecutor.submit( new Callable() { @Override...

HDFS-16713. Improve code with Lambda in org.apache.hadoop.hdfs.server.namenode sub packages

5

### Description of PR Improve Code with Lambda in org.apahce.hadoop.hdfs.server.namenode sub packages. For example: Current logic: ``` public ListenableFuture getJournaledEdits( long fromTxnId, int maxTransactions) { return parallelExecutor.submit( new Callable() {...

HDFS-16710. Remove redundant throw exceptions in org.apache.hadoop.hdfs.server.namenode package

8

### Description of PR When I read some class about HDFS NameNode, I found there are many redundant throw exception in org.apahce.hadoop.hdfs.server.namenode package, such as: ``` public synchronized void transitionToObserver(StateChangeRequestInfo...

HDFS-16717. Replace NPE with IOException in DataNode.class

3

### Description of PR In current logic, if storage not yet initialized, it will throw a NPE in DataNode.class. Developers or SREs are very sensitive to NPE, so I feel...

HDFS-16704. Datanode return empty response instead of NPE for GetVolumeInfo during restarting

7

### Description of PR During datanode starting, I found some NPE in logs: ``` Caused by: java.lang.NullPointerException: Storage not yet initialized     at org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkNotNull(Preconditions.java:899)     at org.apache.hadoop.hdfs.server.datanode.DataNode.getVolumeInfo(DataNode.java:3533)     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)    ...

HDFS-16718. Improve Code with Lambda in org.apache.hadoop.hdfs.server.datanode packages

4

### Description of PR Improve Code with Lambda in org.apahce.hadoop.hdfs.server.datanode packages. For example: Current logic: ``` synchronized void startAll() throws IOException { try { UserGroupInformation.getLoginUser().doAs( new PrivilegedExceptionAction() { @Override public...