##### General

- Overview
- Single Node Setup
- Cluster Setup
- Commands Reference
- FileSystem Shell
- Compatibility Specification
- Downstream Developer's Guide
- Admin Compatibility Guide
- Interface Classification
- FileSystem Specification

##### Common

- CLI Mini Cluster
- Native Libraries
- Proxy User
- Rack Awareness
- Secure Mode
- Service Level Authorization
- HTTP Authentication
- Credential Provider API
- Hadoop KMS
- Tracing
- Unix Shell Guide

##### HDFS

- Architecture
- User Guide
- Commands Reference
- NameNode HA With QJM
- NameNode HA With NFS
- Observer NameNode
- Federation
- ViewFs
- ViewFsOverloadScheme
- Snapshots
- Edits Viewer
- Image Viewer
- Permissions and HDFS
- Quotas and HDFS
- libhdfs (C API)
- WebHDFS (REST API)
- HttpFS
- Short Circuit Local Reads
- Centralized Cache Management
- NFS Gateway
- Rolling Upgrade
- Extended Attributes
- Transparent Encryption
- Multihoming
- Storage Policies
- Memory Storage Support
- Synthetic Load Generator
- Erasure Coding
- Disk Balancer
- Upgrade Domain
- DataNode Admin
- Router Federation
- Provided Storage

##### MapReduce

- Tutorial
- Commands Reference
- Compatibility with 1.x
- Encrypted Shuffle
- Pluggable Shuffle/Sort
- Distributed Cache Deploy
- Support for YARN Shared Cache

##### MapReduce REST APIs

- MR Application Master
- MR History Server

##### YARN

- Architecture
- Commands Reference
- Capacity Scheduler
- Fair Scheduler
- ResourceManager Restart
- ResourceManager HA
- Resource Model
- Node Labels
- Node Attributes
- Web Application Proxy
- Timeline Server
- Timeline Service V.2
- Writing YARN Applications
- YARN Application Security
- NodeManager
- Running Applications in Docker Containers
- Using CGroups
- Secure Containers
- Registry
- Reservation System
- Graceful Decommission
- Opportunistic Containers
- YARN Federation
- Shared Cache
- Using GPU
- Using FPGA
- Placement Constraints
- YARN UI2

##### YARN REST APIs

- Introduction
- Resource Manager
- Node Manager
- Timeline Server
- Timeline Service V.2

##### YARN Service

- Overview
- QuickStart
- Concepts
- Yarn Service API
- Service Discovery
- System Services

##### Submarine

- Index
- QuickStart
- Examples

##### Hadoop Compatible File Systems

- Aliyun OSS
- Amazon S3
- Azure Blob Storage
- Azure Data Lake Storage
- OpenStack Swift

##### Auth

- Overview
- Examples
- Configuration
- Building

##### Tools

- Hadoop Streaming
- Hadoop Archives
- Hadoop Archive Logs
- DistCp
- GridMix
- Rumen
- Resource Estimator Service
- Scheduler Load Simulator
- Hadoop Benchmarking

##### Reference

- Changelog and Release Notes
- Java API docs
- Unix Shell API
- Metrics

##### Configuration

- core-default.xml
- hdfs-default.xml
- hdfs-rbf-default.xml
- mapred-default.xml
- yarn-default.xml
- kms-default.xml
- httpfs-default.xml
- Deprecated Properties

# Apache Hadoop Changelog

## Release 2.7.3 - 2016-08-25

### INCOMPATIBLE CHANGES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-11252 | RPC client does not time out by default | Critical | ipc | Wilfred Spiegelenburg | Masatake Iwasaki

### IMPORTANT ISSUES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-4785 | inconsistent value type of the “type” field for LeafQueueInfo in response of RM REST API - cluster/scheduler | Major | webapp | Jayesh | Varun Vasudev

### IMPROVEMENTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HDFS-2580 | NameNode#main(…) can make use of GenericOptionsParser. | Minor | namenode | Harsh J | Harsh J
HDFS-8101 | DFSClient use of non-constant DFSConfigKeys pulls in WebHDFS classes at runtime | Minor | hdfs-client | Sean Busbey | Sean Busbey
YARN-3404 | View the queue name to YARN Application page | Minor | . | Ryu Kobayashi | Ryu Kobayashi
HDFS-8647 | Abstract BlockManager’s rack policy into BlockPlacementPolicy | Major | . | Ming Ma | Brahma Reddy Battula
MAPREDUCE-5485 | Allow repeating job commit by extending OutputCommitter API | Critical | . | Nemon Lou | Junping Du
HDFS-9314 | Improve BlockPlacementPolicyDefault’s picking of excess replicas | Major | . | Ming Ma | Xiao Chen
MAPREDUCE-6436 | JobHistory cache issue | Blocker | . | Ryu Kobayashi | Kai Sasaki
HDFS-9198 | Coalesce IBR processing in the NN | Major | namenode | Daryn Sharp | Daryn Sharp
HADOOP-12570 | HDFS Secure Mode Documentation updates | Major | documentation | Arpit Agarwal | Arpit Agarwal
HDFS-9569 | Log the name of the fsimage being loaded for better supportability | Trivial | namenode | Yongjun Zhang | Yongjun Zhang
HDFS-9415 | Document dfs.cluster.administrators and dfs.permissions.superusergroup | Major | documentation | Arpit Agarwal | Xiaobing Zhou
YARN-4492 | Add documentation for preemption supported in Capacity scheduler | Minor | capacity scheduler | Naganarasimha G R | Naganarasimha G R
HDFS-9654 | Code refactoring for HDFS-8578 | Minor | datanode | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HDFS-9669 | TcpPeerServer should respect ipc.server.listen.queue.size | Major | . | Elliott Clark | Elliott Clark
HDFS-9629 | Update the footer of Web UI to show year 2016 | Major | . | Xiao Chen | Xiao Chen
HADOOP-12772 | NetworkTopologyWithNodeGroup.getNodeGroup() can loop infinitely for invalid ‘loc’ values | Minor | . | Kuhu Shukla | Kuhu Shukla
HADOOP-12805 | Annotate CanUnbuffer with @InterfaceAudience.Public | Major | . | Ted Yu | Ted Yu
YARN-4690 | Skip object allocation in FSAppAttempt#getResourceUsage when possible | Major | . | Ming Ma | Ming Ma
HDFS-4946 | Allow preferLocalNode in BlockPlacementPolicyDefault to be configurable | Major | namenode | James Kinley | Nathan Roberts
HADOOP-12794 | Support additional compression levels for GzipCodec | Major | io | Ravi Mutyala | Ravi Mutyala
HADOOP-12800 | Copy docker directory from 2.8 to 2.7/2.6 repos to enable pre-commit Jenkins runs | Major | build, yetus | Zhe Zhang | Zhe Zhang
HDFS-8578 | On upgrade, Datanode should process all storage/data dirs in parallel | Critical | datanode | Raju Bairishetti | Vinayakumar B
MAPREDUCE-6622 | Add capability to set JHS job cache to a task-based limit | Critical | jobhistoryserver | Ray Chiang | Ray Chiang
HDFS-9906 | Remove spammy log spew when a datanode is restarted | Major | namenode | Elliott Clark | Brahma Reddy Battula
HADOOP-12789 | log classpath of ApplicationClassLoader at INFO level | Minor | util | Sangjin Lee | Sangjin Lee
HDFS-9860 | Backport HDFS-9638 to branch-2.7. | Major | distcp, documentation | Gary Steelman | Wei-Chiu Chuang
HDFS-10264 | Logging improvements in FSImageFormatProtobuf.Saver | Major | namenode | Konstantin Shvachko | Xiaobing Zhou
HADOOP-13039 | Add documentation for configuration property ipc.maximum.data.length for controlling maximum RPC message size. | Major | documentation | Chris Nauroth | Mingliang Liu
HADOOP-13103 | Group resolution from LDAP may fail on javax.naming.ServiceUnavailableException | Minor | security | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HDFS-10488 | Update WebHDFS documentation regarding CREATE and MKDIR default permissions | Minor | documentation, webhdfs | Wellington Chevreuil | Wellington Chevreuil
HADOOP-13298 | Fix the leftover L&N files in hadoop-build-tools/src/main/resources/META-INF/ | Minor | . | Xiao Chen | Tsuyoshi Ozawa

### BUG FIXES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-8818 | Should use equals() rather than == to compare String or Text in MD5MD5CRC32FileChecksum and TFileDumper | Minor | fs, io | Brandon Li | Brandon Li
HADOOP-9121 | InodeTree.java has redundant check for vName while throwing exception | Major | fs | Arup Malakar | Arup Malakar
HADOOP-7817 | RawLocalFileSystem.append() should give FSDataOutputStream with accurate .getPos() | Major | fs | Kristofer Tomasette | Kanaka Kumar Avvaru
MAPREDUCE-6413 | TestLocalJobSubmission is failing with unknown host | Major | test | Jason Lowe | zhihai xu
YARN-3695 | ServerProxy (NMProxy, etc.) shouldn’t retry forever for non network exception. | Major | . | Junping Du | Raju Bairishetti
HADOOP-12107 | long running apps may have a huge number of StatisticsData instances under FileSystem | Critical | fs | Sangjin Lee | Sangjin Lee
YARN-3849 | Too much of preemption activity causing continuos killing of containers across queues | Critical | capacityscheduler | Sunil Govindan | Sunil Govindan
HDFS-8772 | Fix TestStandbyIsHot#testDatanodeRestarts which occasionally fails | Major | . | Walter Su | Walter Su
MAPREDUCE-5817 | Mappers get rescheduled on node transition even after all reducers are completed | Major | applicationmaster | Sangjin Lee | Sangjin Lee
HDFS-8845 | DiskChecker should not traverse the entire tree | Major | . | Chang Li | Chang Li
YARN-4121 | Typos in capacity scheduler documentation. | Trivial | documentation | Kai Sasaki | Kai Sasaki
HDFS-8581 | ContentSummary on / skips further counts on yielding lock | Minor | namenode | tongshiquan | J.Andreina
HADOOP-12348 | MetricsSystemImpl creates MetricsSourceAdapter with wrong time unit parameter. | Major | metrics | zhihai xu | zhihai xu
HADOOP-12374 | Description of hdfs expunge command is confusing | Major | documentation, trash | Weiwei Yang | Weiwei Yang
HDFS-9072 | Fix random failures in TestJMXGet | Critical | test | J.Andreina | J.Andreina
MAPREDUCE-6460 | TestRMContainerAllocator.testAttemptNotFoundCausesRMCommunicatorException fails | Major | test | zhihai xu | zhihai xu
MAPREDUCE-6302 | Preempt reducers after a configurable timeout irrespective of headroom | Critical | . | mai shurong | Karthik Kambatla
YARN-4288 | NodeManager restart should keep retrying to register to RM while connection exception happens during RM failed over. | Critical | nodemanager | Junping Du | Junping Du
HDFS-9313 | Possible NullPointerException in BlockManager if no excess replica can be chosen | Major | . | Ming Ma | Ming Ma
HADOOP-12296 | when setnetgrent returns 0 in linux, exception should be thrown | Major | . | Chang Li | Chang Li
HDFS-4937 | ReplicationMonitor can infinite-loop in BlockPlacementPolicyDefault#chooseRandom() | Major | namenode | Kihwal Lee | Kihwal Lee
HDFS-6481 | DatanodeManager#getDatanodeStorageInfos() should check the length of storageIDs | Minor | namenode | Ted Yu | Tsz Wo Nicholas Sze
HDFS-9383 | TestByteArrayManager#testByteArrayManager fails | Major | . | Kihwal Lee | Tsz Wo Nicholas Sze
HADOOP-12482 | Race condition in JMX cache update | Major | . | Tony Wu | Tony Wu
YARN-4347 | Resource manager fails with Null pointer exception | Major | yarn | Yesha Vora | Jian He
HADOOP-12545 | Hadoop javadoc has broken links for AccessControlList, ImpersonationProvider, DefaultImpersonationProvider, and DistCp | Major | documentation | Mohammad Arshad | Mohammad Arshad
YARN-4374 | RM capacity scheduler UI rounds user limit factor | Major | capacityscheduler | Chang Li | Chang Li
YARN-3769 | Consider user limit when calculating total pending resource for preemption policy in Capacity Scheduler | Major | capacityscheduler | Eric Payne | Eric Payne
YARN-4380 | TestResourceLocalizationService.testDownloadingResourcesOnContainerKill fails intermittently | Major | test | Tsuyoshi Ozawa | Varun Saxena
YARN-4398 | Yarn recover functionality causes the cluster running slowly and the cluster usage rate is far below 100 | Major | resourcemanager | NING DING | NING DING
HADOOP-12565 | Replace DSA with RSA for SSH key type in SingleCluster.md | Minor | documentation | Alexander Veit | Mingliang Liu
YARN-4422 | Generic AHS sometimes doesn’t show started, node, or logs on App page | Major | . | Eric Payne | Eric Payne
HADOOP-12602 | TestMetricsSystemImpl#testQSize occasionally fail | Major | test | Wei-Chiu Chuang | Masatake Iwasaki
YARN-4439 | Clarify NMContainerStatus#toString method. | Major | . | Jian He | Jian He
HDFS-9516 | truncate file fails with data dirs on multiple disks | Major | datanode | Bogdan Raducanu | Plamen Jeliazkov
YARN-4452 | NPE when submit Unmanaged application | Critical | . | Naganarasimha G R | Naganarasimha G R
HDFS-9533 | seen_txid in the shared edits directory is modified during bootstrapping | Major | ha, namenode | Kihwal Lee | Kihwal Lee
HDFS-9347 | Invariant assumption in TestQuorumJournalManager.shutdown() is wrong | Major | test | Wei-Chiu Chuang | Wei-Chiu Chuang
HADOOP-12636 | Prevent ServiceLoader failure init for unused FileSystems | Major | fs | Íñigo Goiri | Íñigo Goiri
MAPREDUCE-6583 | Clarify confusing sentence in MapReduce tutorial document | Minor | documentation | chris snow | Kai Sasaki
HDFS-9505 | HDFS Architecture documentation needs to be refreshed. | Major | documentation | Chris Nauroth | Masatake Iwasaki
HDFS-7163 | WebHdfsFileSystem should retry reads according to the configured retry policy. | Major | webhdfs | Eric Payne | Eric Payne
HADOOP-12559 | KMS connection failures should trigger TGT renewal | Major | security | Zhe Zhang | Zhe Zhang
HADOOP-12682 | Fix TestKMS#testKMSRestart* failure | Major | . | Wei-Chiu Chuang | Wei-Chiu Chuang
MAPREDUCE-6577 | MR AM unable to load native library without MR_AM_ADMIN_USER_ENV set | Critical | mr-am | Sangjin Lee | Sangjin Lee
YARN-4546 | ResourceManager crash due to scheduling opportunity overflow | Critical | resourcemanager | Jason Lowe | Jason Lowe
HDFS-9600 | do not check replication if the block is under construction | Critical | . | Phil Yang | Phil Yang
HADOOP-12613 | TestFind.processArguments occasionally fails | Major | test | Wei-Chiu Chuang | Wei-Chiu Chuang
YARN-4414 | Nodemanager connection errors are retried at multiple levels | Major | nodemanager | Jason Lowe | Chang Li
HDFS-9648 | TestStartup.testImageChecksum is broken by HDFS-9569’s message change | Trivial | namenode | Wei-Chiu Chuang | Wei-Chiu Chuang
HADOOP-12706 | TestLocalFsFCStatistics#testStatisticsThreadLocalDataCleanUp times out occasionally | Major | test | Jason Lowe | Sangjin Lee
YARN-4581 | AHS writer thread leak makes RM crash while RM is recovering | Major | resourcemanager | sandflee | sandflee
MAPREDUCE-6554 | MRAppMaster servicestart failing with NPE in MRAppMaster#parsePreviousJobHistory | Critical | . | Bibin A Chundatt | Bibin A Chundatt
HDFS-9661 | Deadlock in DN.FsDatasetImpl between moveBlockAcrossStorage and createRbw | Major | datanode | ade | ade
HDFS-9625 | set replication for empty file failed when set storage policy | Major | namenode | DENG FEI | DENG FEI
HDFS-9634 | webhdfs client side exceptions don’t provide enough details | Major | webhdfs | Eric Payne | Eric Payne
YARN-4610 | Reservations continue looking for one app causes other apps to starve | Blocker | capacityscheduler | Jason Lowe | Jason Lowe
YARN-4598 | Invalid event: RESOURCE_FAILED at CONTAINER_CLEANEDUP_AFTER_KILL | Major | nodemanager | tangshangwen | tangshangwen
HDFS-9690 | ClientProtocol.addBlock is not idempotent after HDFS-8071 | Major | namenode | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
MAPREDUCE-6619 | HADOOP_CLASSPATH is overwritten in MR container | Major | mrv2 | shanyu zhao | Junping Du
YARN-4428 | Redirect RM page to AHS page when AHS turned on and RM page is not available | Major | . | Chang Li | Chang Li
MAPREDUCE-6618 | YarnClientProtocolProvider leaking the YarnClient thread. | Major | . | Xuan Gong | Xuan Gong
YARN-3102 | Decommisioned Nodes not listed in Web UI | Minor | resourcemanager | Bibin A Chundatt | Kuhu Shukla
HDFS-9406 | FSImage may get corrupted after deleting snapshot | Major | namenode | Stanislav Antic | Yongjun Zhang
MAPREDUCE-6621 | Memory Leak in JobClient#submitJobInternal() | Major | . | Xuan Gong | Xuan Gong
HDFS-9740 | Use a reasonable limit in DFSTestUtil.waitForMetric() | Major | test | Kihwal Lee | Chang Li
HADOOP-12761 | incremental maven build is not really incremental | Minor | build | Sangjin Lee | Sangjin Lee
HDFS-9743 | Fix TestLazyPersistFiles#testFallbackToDiskFull in branch-2.7 | Major | . | Kihwal Lee | Kihwal Lee
HDFS-9730 | Storage ID update does not happen when there is a layout change | Major | datanode | Kihwal Lee | Tsz Wo Nicholas Sze
HDFS-9724 | Degraded performance in WebHDFS listing as it does not reuse ObjectMapper | Critical | performance | Akira Ajisaka | Akira Ajisaka
HADOOP-12773 | HBase classes fail to load with client/job classloader enabled | Major | util | Sangjin Lee | Sangjin Lee
HDFS-9784 | Example usage is not correct in Transparent Encryption document | Major | documentation | Takashi Ohnishi | Takashi Ohnishi
HDFS-9752 | Permanent write failures may happen to slow writers during datanode rolling upgrades | Critical | . | Kihwal Lee | Walter Su
HDFS-9779 | TestReplicationPolicyWithNodeGroup NODE variable picks wrong rack value | Minor | test | Kuhu Shukla | Kuhu Shukla
HADOOP-12792 | TestUserGroupInformation#testGetServerSideGroups fails in chroot | Minor | security, test | Eric Badger | Eric Badger
HADOOP-12589 | Fix intermittent test failure of TestCopyPreserveFlag | Major | test | Tsuyoshi Ozawa | Masatake Iwasaki
HADOOP-12786 | “hadoop key” command usage is not documented | Major | documentation | Akira Ajisaka | Xiao Chen
HDFS-9765 | TestBlockScanner#testVolumeIteratorWithCaching fails intermittently | Major | test | Mingliang Liu | Akira Ajisaka
HADOOP-12810 | FileSystem#listLocatedStatus causes unnecessary RPC calls | Major | fs, fs/s3 | Ryan Blue | Ryan Blue
MAPREDUCE-6637 | Testcase Failure : TestFileInputFormat.testSplitLocationInfo | Major | test | Brahma Reddy Battula | Brahma Reddy Battula
YARN-4707 | Remove the extra char (>) from SecureContainer.md | Major | documentation | Brahma Reddy Battula | Brahma Reddy Battula
MAPREDUCE-6635 | Unsafe long to int conversion in UncompressedSplitLineReader and IndexOutOfBoundsException | Critical | . | Sergey Shelukhin | Junping Du
YARN-2046 | Out of band heartbeats are sent only on container kill and possibly too early | Major | nodemanager | Jason Lowe | Ming Ma
YARN-4722 | AsyncDispatcher logs redundant event queue sizes | Major | . | Jason Lowe | Jason Lowe
YARN-4723 | NodesListManager$UnknownNodeId ClassCastException | Critical | resourcemanager | Jason Lowe | Kuhu Shukla
HDFS-9864 | Correct reference for RENEWDELEGATIONTOKEN and CANCELDELEGATIONTOKEN in webhdfs doc | Major | documentation | Brahma Reddy Battula | Brahma Reddy Battula
HDFS-9880 | TestDatanodeRegistration fails occasionally | Major | test | Kihwal Lee | Kihwal Lee
HDFS-9766 | TestDataNodeMetrics#testDataNodeTimeSpend fails intermittently | Major | test | Mingliang Liu | Xiao Chen
HDFS-9851 | Name node throws NPE when setPermission is called on a path that does not exist | Critical | namenode | David Yan | Brahma Reddy Battula
HADOOP-12870 | Fix typo admininistration in CommandsManual.md | Minor | documentation | Akira Ajisaka | John Zhuge
HDFS-9048 | DistCp documentation is out-of-dated | Major | . | Haohui Mai | Daisuke Kobayashi
HADOOP-12871 | Fix dead link to NativeLibraries.html in CommandsManual.md | Minor | documentation | Akira Ajisaka | Brahma Reddy Battula
HADOOP-12872 | Fix formatting in ServiceLevelAuth.md | Trivial | documentation | Akira Ajisaka | Brahma Reddy Battula
MAPREDUCE-4785 | TestMRApp occasionally fails | Major | mrv2, test | Jason Lowe | Haibo Chen
YARN-4761 | NMs reconnecting with changed capabilities can lead to wrong cluster resource calculations on fair scheduler | Major | fairscheduler | Sangjin Lee | Sangjin Lee
YARN-4760 | proxy redirect to history server uses wrong URL | Major | webapp | Jason Lowe | Eric Badger
HDFS-9865 | TestBlockReplacement fails intermittently in trunk | Major | test | Yiqun Lin | Yiqun Lin
HDFS-9812 | Streamer threads leak if failure happens when closing DFSOutputStream | Major | hdfs-client | Yiqun Lin | Yiqun Lin
HADOOP-12688 | Fix deadlinks in Compatibility.md | Major | documentation | Akira Ajisaka | Gabor Liptak
HDFS-9904 | testCheckpointCancellationDuringUpload occasionally fails | Major | test | Kihwal Lee | Yiqun Lin
MAPREDUCE-6645 | TestWordStats outputs logs under directories other than target/test-dir | Major | test | Akira Ajisaka | Gabor Liptak
HDFS-9874 | Long living DataXceiver threads cause volume shutdown to block. | Critical | datanode | Rushabh S Shah | Rushabh S Shah
YARN-4686 | MiniYARNCluster.start() returns before cluster is completely started | Major | test | Rohith Sharma K S | Eric Badger
MAPREDUCE-6363 | [NNBench] Lease mismatch error when running with multiple mappers | Critical | benchmarks | Brahma Reddy Battula | Bibin A Chundatt
MAPREDUCE-6580 | Test failure : TestMRJobsWithProfiler | Major | . | Rohith Sharma K S | Eric Badger
MAPREDUCE-6656 | [NNBench] OP_DELETE operation isn’t working after MAPREDUCE-6363 | Blocker | . | J.Andreina | J.Andreina
YARN-4850 | test-fair-scheduler.xml isn’t valid xml | Blocker | fairscheduler, test | Allen Wittenauer | Yufei Gu
HADOOP-12958 | PhantomReference for filesystem statistics can trigger OOM | Major | . | Jason Lowe | Sangjin Lee
HDFS-10182 | Hedged read might overwrite user’s buf | Major | . | zhouyingchao | zhouyingchao
YARN-4773 | Log aggregation performs extraneous filesystem operations when rolling log aggregation is disabled | Minor | nodemanager | Jason Lowe | Jun Gong
HDFS-9478 | Reason for failing ipc.FairCallQueue contruction should be thrown | Minor | . | Archana T | Ajith S
HADOOP-12902 | JavaDocs for SignerSecretProvider are out-of-date in AuthenticationFilter | Major | documentation | Robert Kanter | Gabor Liptak
YARN-4183 | Clarify the behavior of timeline service config properties | Major | . | Mit Desai | Naganarasimha G R
YARN-4706 | UI Hosting Configuration in TimelineServer doc is broken | Critical | documentation | Akira Ajisaka | Akira Ajisaka
HDFS-10178 | Permanent write failures can happen if pipeline recoveries occur for the first packet | Critical | . | Kihwal Lee | Kihwal Lee
HDFS-9917 | IBR accumulate more objects when SNN was down for sometime. | Critical | . | Brahma Reddy Battula | Brahma Reddy Battula
HDFS-10239 | Fsshell mv fails if port usage doesn’t match in src and destination paths | Major | . | Kuhu Shukla | Kuhu Shukla
YARN-4915 | Fix typo in YARN Secure Containers documentation | Trivial | documentation, yarn | Takashi Ohnishi | Takashi Ohnishi
YARN-4917 | Fix typos in documentation of Capacity Scheduler. | Minor | documentation | Takashi Ohnishi | Takashi Ohnishi
HDFS-10261 | TestBookKeeperHACheckpoints doesn’t handle ephemeral HTTP ports | Major | . | Eric Badger | Eric Badger
MAPREDUCE-6670 | TestJobListCache#testEviction sometimes fails on Windows with timeout | Minor | test | Gergely Novák | Gergely Novák
MAPREDUCE-6633 | AM should retry map attempts if the reduce task encounters commpression related errors. | Major | . | Rushabh S Shah | Rushabh S Shah
YARN-4938 | MiniYarnCluster should not request transitionToActive to RM on non-HA environment | Major | test | Akira Ajisaka | Eric Badger
HADOOP-12406 | AbstractMapWritable.readFields throws ClassNotFoundException with custom writables | Blocker | io | Nadeem Douba | Nadeem Douba
HDFS-10271 | Extra bytes are getting released from reservedSpace for append | Critical | . | Brahma Reddy Battula | Brahma Reddy Battula
YARN-4794 | Deadlock in NMClientImpl | Critical | . | Sumana Sathish | Jian He
HDFS-9772 | TestBlockReplacement#testThrottler doesn’t work as expected | Minor | test | Yiqun Lin | Yiqun Lin
YARN-4924 | NM recovery race can lead to container not cleaned up | Major | nodemanager | Nathan Roberts | sandflee
HADOOP-12989 | Some tests in org.apache.hadoop.fs.shell.find occasionally time out | Major | test | Akira Ajisaka | Takashi Ohnishi
YARN-4940 | yarn node -list -all failed if RM start with decommissioned node | Major | . | sandflee | sandflee
HDFS-10275 | TestDataNodeMetrics failing intermittently due to TotalWriteTime counted incorrectly | Major | test | Yiqun Lin | Yiqun Lin
MAPREDUCE-6680 | JHS UserLogDir scan algorithm sometime could skip directory with update in CloudFS (Azure FileSystem, S3, etc.) | Major | jobhistoryserver | Junping Du | Junping Du
HADOOP-13042 | Restore lost leveldbjni LICENSE and NOTICE changes | Major | . | Andrew Wang | Andrew Wang
HADOOP-13043 | Add LICENSE.txt entries for bundled javascript dependencies | Major | . | Andrew Wang | Andrew Wang
HDFS-10319 | Balancer should not try to pair storages with different types | Minor | balancer & mover | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HDFS-9555 | LazyPersistFileScrubber should still sleep if there are errors in the clear progress | Major | . | Phil Yang | Phil Yang
HADOOP-13052 | ChecksumFileSystem mishandles crc file permissions | Major | fs | Daryn Sharp | Daryn Sharp
HDFS-9905 | WebHdfsFileSystem#runWithRetry should display original stack trace on error | Major | test | Kihwal Lee | Wei-Chiu Chuang
HDFS-10245 | Fix the findbug warnings in branch-2.7 | Major | . | Brahma Reddy Battula | Brahma Reddy Battula
YARN-4556 | TestFifoScheduler.testResourceOverCommit fails | Major | scheduler, test | Akihiro Suda | Akihiro Suda
HDFS-9958 | BlockManager#createLocatedBlocks can throw NPE for corruptBlocks on failed storages. | Major | . | Kuhu Shukla | Kuhu Shukla
YARN-5008 | LeveldbRMStateStore database can grow substantially leading to long recovery times | Major | resourcemanager | Jason Lowe | Jason Lowe
YARN-5009 | NMLeveldbStateStoreService database can grow substantially leading to longer recovery times | Major | nodemanager | Jason Lowe | Jason Lowe
HDFS-10335 | Mover$Processor#chooseTarget() always chooses the first matching target storage group | Critical | balancer & mover | Mingliang Liu | Mingliang Liu
HDFS-10347 | Namenode report bad block method doesn’t log the bad block or datanode. | Minor | namenode | Rushabh S Shah | Rushabh S Shah
YARN-4834 | ProcfsBasedProcessTree doesn’t track daemonized processes | Major | nodemanager | Nathan Roberts | Nathan Roberts
MAPREDUCE-6514 | Job hangs as ask is not updated after ramping down of all reducers | Blocker | applicationmaster | Varun Saxena | Varun Saxena
HDFS-2043 | TestHFlush failing intermittently | Major | test | Aaron T. Myers | Yiqun Lin
MAPREDUCE-6689 | MapReduce job can infinitely increase number of reducer resource requests | Blocker | . | Wangda Tan | Wangda Tan
YARN-4747 | AHS error 500 due to NPE when container start event is missing | Major | timelineserver | Jason Lowe | Varun Saxena
HADOOP-13084 | Fix ASF License warnings in branch-2.7 | Major | . | Brahma Reddy Battula | Brahma Reddy Battula
HDFS-10372 | Fix for failing TestFsDatasetImpl#testCleanShutdownOfVolume | Major | test | Rushabh S Shah | Rushabh S Shah
MAPREDUCE-6558 | multibyte delimiters with compressed input files generate duplicate records | Major | mrv1, mrv2 | Wilfred Spiegelenburg | Wilfred Spiegelenburg
MAPREDUCE-6513 | MR job got hanged forever when one NM unstable for some time | Critical | applicationmaster, resourcemanager | Bob.zhao | Varun Saxena
YARN-3840 | Resource Manager web ui issue when sorting application by id (with application having id > 9999) | Major | resourcemanager | LINTE | Varun Saxena
YARN-5055 | max apps per user can be larger than max per queue | Minor | capacityscheduler, resourcemanager | Jason Lowe | Eric Badger
YARN-4751 | In 2.7, Labeled queue usage not shown properly in capacity scheduler UI | Major | capacity scheduler, yarn | Eric Payne | Eric Payne
HDFS-9365 | Balancer does not work with the HDFS-6376 HA setup | Major | balancer & mover | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
YARN-4459 | container-executor should only kill process groups | Major | nodemanager | Jun Gong | Jun Gong
HDFS-9476 | TestDFSUpgradeFromImage#testUpgradeFromRel1BBWImage occasionally fail | Major | . | Wei-Chiu Chuang | Masatake Iwasaki
HDFS-10458 | getFileEncryptionInfo should return quickly for non-encrypted cluster | Major | encryption, namenode | Zhe Zhang | Zhe Zhang
YARN-5206 | RegistrySecurity includes id:pass in exception text if considered invalid | Minor | client, security | Steve Loughran | Steve Loughran
HADOOP-13270 | BZip2CompressionInputStream finds the same compression marker twice in corner case, causing duplicate data blocks | Critical | . | Haibo Chen | Kai Sasaki
HADOOP-13255 | KMSClientProvider should check and renew tgt when doing delegation token operations. | Major | kms | Xiao Chen | Xiao Chen
HDFS-10474 | hftp copy fails when file name with Chinese+special char in branch-2 | Critical | . | Brahma Reddy Battula | Brahma Reddy Battula
HADOOP-13192 | org.apache.hadoop.util.LineReader cannot handle multibyte delimiters correctly | Critical | util | binde | binde
HADOOP-13350 | Additional fix to LICENSE and NOTICE | Blocker | build | Xiao Chen | Xiao Chen
HADOOP-12893 | Verify LICENSE.txt and NOTICE.txt | Blocker | build | Allen Wittenauer | Xiao Chen
HADOOP-13297 | Add missing dependency in setting maven-remote-resource-plugin to fix builds | Major | build | Akira Ajisaka | Sean Busbey
HDFS-10623 | Remove unused import of httpclient.HttpConnection from TestWebHdfsTokens. | Major | hdfs | Jitendra Nath Pandey | Hanisha Koneru
YARN-5309 | Fix SSLFactory truststore reloader thread leak in TimelineClientImpl | Blocker | timelineserver, yarn | Thomas Friedrich | Weiwei Yang
HDFS-8914 | Document HA support in the HDFS HdfsDesign.md | Major | documentation | Ravindra Babu | Lars Francke
HADOOP-12588 | Fix intermittent test failure of TestGangliaMetrics | Major | . | Tsuyoshi Ozawa | Masatake Iwasaki
HADOOP-13434 | Add quoting to Shell class | Major | . | Owen O’Malley | Owen O’Malley
HDFS-9530 | ReservedSpace is not cleared for abandoned Blocks | Critical | datanode | Fei Hui | Brahma Reddy Battula

### TESTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
MAPREDUCE-6191 | TestJavaSerialization fails with getting incorrect MR job result | Minor | test | sam liu | sam liu
YARN-3602 | TestResourceLocalizationService.testPublicResourceInitializesLocalDir fails Intermittently due to IOException from cleanup | Minor | test | zhihai xu | zhihai xu
HADOOP-12736 | TestTimedOutTestsListener#testThreadDumpAndDeadlocks sometimes times out | Major | . | Xiao Chen | Xiao Chen
HADOOP-12715 | TestValueQueue#testgetAtMostPolicyALL fails intermittently | Major | . | Xiao Chen | Xiao Chen
HDFS-9688 | Test the effect of nested encryption zones in HDFS downgrade | Major | encryption, test | Zhe Zhang | Zhe Zhang
YARN-5069 | TestFifoScheduler.testResourceOverCommit race condition | Major | test | Eric Badger | Eric Badger

### SUB-TASKS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-4623 | TestSystemMetricsPublisher#testPublishAppAttemptMetricsForUnmanagedAM fails with NPE | Major | yarn | Jason Lowe | Naganarasimha G R
HDFS-10186 | DirectoryScanner: Improve logs by adding full path of both actual and expected block directories | Minor | datanode | Rakesh R | Rakesh R
HADOOP-13154 | S3AFileSystem printAmazonServiceException/printAmazonClientException appear copy & paste of AWS examples | Blocker | fs/s3 | Steve Loughran | Steve Loughran
YARN-3362 | Add node label usage in RM CapacityScheduler web UI | Major | capacityscheduler, resourcemanager, webapp | Wangda Tan | Naganarasimha G R
YARN-3426 | Add jdiff support to YARN | Blocker | . | Li Lu | Li Lu

### OTHER:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-11814 | Reformat hadoop-annotations, o.a.h.classification.tools | Minor | . | Li Lu | Li Lu
YARN-4653 | Document YARN security model from the perspective of Application Developers | Major | site | Steve Loughran | Steve Loughran
HADOOP-13312 | Update CHANGES.txt to reflect all the changes in branch-2.7 | Blocker | . | Akira Ajisaka | Akira Ajisaka