##### 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 0.1.0 - 2006-04-02

### NEW FEATURES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-37 | A way to determine the size and overall activity of the cluster | Major | . | Owen O’Malley |
HADOOP-80 | binary key | Major | io | Owen O’Malley | Owen O’Malley
HADOOP-44 | RPC exceptions should include remote stack trace | Major | ipc | Doug Cutting | Doug Cutting
HADOOP-46 | user-specified job names | Major | . | Doug Cutting | Owen O’Malley

### IMPROVEMENTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-25 | a new map/reduce example and moving the examples from src/java to src/examples | Minor | . | Owen O’Malley | Owen O’Malley
HADOOP-20 | Mapper, Reducer need an occasion to cleanup after the last record is processed. | Major | . | Michel Tourn |
HADOOP-30 | DFS shell: support for ls -r and cat | Major | . | Michel Tourn |
HADOOP-38 | default splitter should incorporate fs block size | Major | . | Doug Cutting |
HADOOP-36 | Adding some uniformity/convenience to environment management | Major | conf | Bryan Pendleton |
HADOOP-49 | JobClient cannot use a non-default server (unlike DFSShell) | Major | . | Michel Tourn | Michel Tourn
HADOOP-41 | JAVA_OPTS for the TaskRunner Child | Minor | conf | stack |
HADOOP-60 | Specification of alternate conf. directory | Minor | . | stack |
HADOOP-79 | listFiles optimization | Major | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-87 | SequenceFile performance degrades substantially compression is on and large values are encountered | Major | io | Sameer Paranjpye | Doug Cutting
HADOOP-45 | JobTracker should log task errors | Major | . | Doug Cutting | Doug Cutting
HADOOP-67 | Added statistic/reporting info to DFS | Trivial | . | Barry Kaplan | Doug Cutting
HADOOP-33 | DF enhancement: performance and win XP support | Minor | fs | Konstantin Shvachko | Konstantin Shvachko
HADOOP-103 | introduce a common parent class for Mapper and Reducer | Minor | . | Owen O’Malley | Owen O’Malley

### BUG FIXES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-6 | missing build directory in classpath | Minor | . | Owen O’Malley |
HADOOP-7 | MapReduce has a series of problems concerning task-allocation to worker nodes | Major | . | Mike Cafarella |
HADOOP-10 | ndfs.replication is not documented within the nutch-default.xml configuration file. | Trivial | . | Rod Taylor |
HADOOP-5 | need commons-logging-api jar file | Minor | . | Owen O’Malley |
HADOOP-21 | the webapps need to be updated for the move from nutch | Minor | . | Owen O’Malley |
HADOOP-22 | remove unused imports | Trivial | . | Sami Siren |
HADOOP-28 | webapps broken | Major | . | Owen O’Malley |
HADOOP-12 | InputFormat used in job must be in JobTracker classpath (not loaded from job JAR) | Minor | . | Bryan Pendleton |
HADOOP-34 | Build Paths Relative to PWD in build.xml | Trivial | . | Jeremy Bensley |
HADOOP-42 | PositionCache decrements its position for reads at the end of file | Major | fs | Konstantin Shvachko |
HADOOP-40 | bufferSize argument is ignored in FileSystem.create(File, boolean, int) | Minor | fs | Konstantin Shvachko |
HADOOP-16 | RPC call times out while indexing map task is computing splits | Major | . | Chris Schneider | Mike Cafarella
HADOOP-57 | hadoop dfs -ls / does not show root of file system | Minor | . | Yoram Arnon |
HADOOP-66 | dfs client writes all data for a chunk to /tmp | Major | . | Sameer Paranjpye | Doug Cutting
HADOOP-70 | the two file system tests TestDFS and TestFileSystem take too long | Major | . | Owen O’Malley | Owen O’Malley
HADOOP-77 | hang / crash when input folder does not exists. | Critical | . | Stefan Groschupf |
HADOOP-78 | rpc commands not buffered | Major | ipc | Owen O’Malley | Owen O’Malley
HADOOP-81 | speculative execution is only controllable from the default config | Major | . | Owen O’Malley | Owen O’Malley
HADOOP-82 | JobTracker loses it: NoSuchElementException | Minor | . | stack |
HADOOP-86 | If corrupted map outputs, reducers get stuck fetching forever | Major | . | stack | Doug Cutting
HADOOP-93 | allow minimum split size configurable | Major | . | Hairong Kuang | Doug Cutting
HADOOP-97 | DFSShell.cat returns NullPointerException if file does not exist | Major | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-3 | Output directories are not cleaned up before the reduces run | Minor | . | Owen O’Malley | Owen O’Malley
HADOOP-83 | infinite retries accessing a missing block | Major | . | Yoram Arnon | Konstantin Shvachko
HADOOP-52 | mapred input and output dirs must be absolute | Major | . | Doug Cutting | Owen O’Malley
HADOOP-98 | The JobTracker’s count of the number of running maps and reduces is wrong | Major | . | Owen O’Malley | Owen O’Malley
HADOOP-19 | Datanode corruption | Critical | . | Rod Taylor | Doug Cutting
HADOOP-84 | client should report file name in which IO exception occurs | Minor | . | Yoram Arnon | Konstantin Shvachko
HADOOP-2 | Reused Keys and Values fail with a Combiner | Major | . | Owen O’Malley | Owen O’Malley
HADOOP-110 | new key and value instances are allocated before each map | Major | . | Owen O’Malley | Owen O’Malley
HADOOP-107 | Namenode errors “Failed to complete filename.crc because dir.getFile()==null and null” | Major | . | Igor Bolotin | Doug Cutting
HADOOP-100 | Inconsistent locking of the JobTracker.taskTrackers field | Major | . | Owen O’Malley | Owen O’Malley
HADOOP-102 | Two identical consecutive loops in FSNamesystem.chooseTarget() | Major | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-112 | copyFromLocal should exclude .crc files | Minor | . | Monu Ogbe | Doug Cutting

### OTHER:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-1 | initial import of code from Nutch | Major | . | Doug Cutting | Doug Cutting