##### 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 0.18.3 - 2009-01-29

### INCOMPATIBLE CHANGES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-4061 | Large number of decommission freezes the Namenode | Major | . | Koji Noguchi | Tsz Wo Nicholas Sze
HADOOP-4659 | Root cause of connection failure is being lost to code that uses it for delaying startup | Blocker | ipc | Steve Loughran | Steve Loughran
HADOOP-4997 | workaround for tmp file handling on DataNodes in 0.18 (HADOOP-4663) | Blocker | . | Raghu Angadi | Raghu Angadi

### IMPROVEMENTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-3780 | JobTracker should synchronously resolve the tasktracker’s network location when the tracker registers | Major | . | Amar Kamat | Amar Kamat

### BUG FIXES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-4257 | TestLeaseRecovery2.testBlockSynchronization failing. | Blocker | test | Vinod Kumar Vavilapalli | Tsz Wo Nicholas Sze
HADOOP-4499 | DFSClient should invoke checksumOk only once. | Blocker | . | Raghu Angadi | Raghu Angadi
HADOOP-4597 | Under-replicated blocks are not calculated if the name-node is forced out of safe-mode. | Blocker | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-4610 | Always calculate mis-replicated blocks when safe-mode is turned off. | Major | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-3121 | dfs -lsr fail with "Could not get listing " | Minor | fs | Koji Noguchi | Tsz Wo Nicholas Sze
HADOOP-3883 | TestFileCreation fails once in a while | Blocker | test | Lohit Vijayarenu | Tsz Wo Nicholas Sze
HADOOP-4556 | Block went missing | Major | . | Robert Chansler | Hairong Kuang
HADOOP-4643 | NameNode should exclude excessive replicas when counting live replicas for a block | Major | . | Hairong Kuang | Hairong Kuang
HADOOP-4703 | DataNode.createInterDataNodeProtocolProxy should not wait for proxy forever while recovering lease | Major | . | Hairong Kuang | Tsz Wo Nicholas Sze
HADOOP-4647 | NamenodeFsck creates a new DFSClient but never closes it | Major | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4616 | assertion makes fuse-dfs exit when reading incomplete data | Blocker | . | Marc-Olivier Fleury | Pete Wyckoff
HADOOP-4614 | “Too many open files” error while processing a large gzip file | Blocker | . | Abdul Qadeer | Yuri Pradkin
HADOOP-4542 | Fault in TestDistributedUpgrade | Minor | test | Robert Chansler | Raghu Angadi
HADOOP-4713 | librecordio does not scale to large records | Blocker | record | Christian Kunz | Christian Kunz
HADOOP-4635 | Memory leak ? | Blocker | . | Marc-Olivier Fleury | Pete Wyckoff
HADOOP-4714 | map tasks timing out during merge phase | Major | . | Christian Kunz | Jothi Padmanabhan
HADOOP-4726 | documentation typos: “the the” | Minor | documentation | Tsz Wo Nicholas Sze | Edward J. Yoon
HADOOP-4679 | Datanode prints tons of log messages: Waiting for threadgroup to exit, active theads is XX | Major | . | Hairong Kuang | Hairong Kuang
HADOOP-4734 | Some lease recovery codes in 0.19 or trunk should also be committed in 0.18. | Blocker | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4746 | Job output directory should be normalized | Blocker | . | Hairong Kuang | Hairong Kuang
HADOOP-4654 | remove temporary output directory of failed tasks | Major | . | Christian Kunz | Amareshwari Sriramadasu
HADOOP-4717 | Removal of default port# in NameNode.getUri() cause a map/reduce job failed to prompt temporay output | Blocker | . | Hairong Kuang | Hairong Kuang
HADOOP-4778 | Check for zero size block meta file when updating a block. | Blocker | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4742 | Mistake delete replica in hadoop 0.18.1 | Blocker | . | Wang Xu | Wang Xu
HADOOP-4702 | Failed block replication leaves an incomplete block in receiver’s tmp data directory | Blocker | . | Hairong Kuang | Hairong Kuang
HADOOP-4613 | browseBlock.jsp does not generate “genstamp” property. | Major | . | Konstantin Shvachko | Johan Oskarsson
HADOOP-4806 | HDFS rename does not work correctly if src contains Java regular expression special characters | Blocker | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4795 | Lease monitor may get into an infinite loop | Blocker | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4822 | 0.18 cannot be compiled in Java 5. | Blocker | util | Tsz Wo Nicholas Sze |
HADOOP-4620 | Streaming mapper never completes if the mapper does not write to stdout | Major | . | Runping Qi | Ravi Gummadi
HADOOP-4810 | Data lost at cluster startup time | Blocker | . | Hairong Kuang | Hairong Kuang
HADOOP-4797 | RPC Server can leave a lot of direct buffers | Blocker | ipc | Raghu Angadi | Raghu Angadi
HADOOP-4840 | TestNodeCount sometimes fails with NullPointerException | Major | . | Hairong Kuang | Hairong Kuang
HADOOP-4904 | Deadlock while leaving safe mode. | Blocker | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-4919 | [HOD] Provide execute access to JT history directory path for group | Major | contrib/hod | Hemanth Yamijala | Peeyush Bishnoi
HADOOP-1980 | ‘dfsadmin -safemode enter’ should prevent the namenode from leaving safemode automatically after startup | Minor | . | Koji Noguchi | Konstantin Shvachko
HADOOP-4924 | Race condition in re-init of TaskTracker | Blocker | . | Devaraj Das | Devaraj Das
HADOOP-4935 | Manual leaving of safe mode may lead to data lost | Major | . | Hairong Kuang | Konstantin Shvachko
HADOOP-4951 | Lease monitor does not own the LeaseManager lock in changing leases. | Blocker | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4961 | ConcurrentModificationException in lease recovery of empty files. | Blocker | . | Konstantin Shvachko | Konstantin Shvachko
HADOOP-4971 | Block report times from datanodes could converge to same time. | Blocker | . | Raghu Angadi | Raghu Angadi
HADOOP-4910 | NameNode should exclude corrupt replicas when choosing excessive replicas to delete | Blocker | . | Hairong Kuang | Hairong Kuang
HADOOP-5077 | JavaDoc errors in 0.18.3 | Blocker | util | Raghu Angadi | Raghu Angadi
HADOOP-4983 | Job counters sometimes go down as tasks run without task failures | Critical | . | Owen O’Malley | Amareshwari Sriramadasu

### SUB-TASKS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-4823 | Should not use java.util.NavigableMap in 0.18 | Major | util | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze
HADOOP-4824 | Should not use File.setWritable(..) in 0.18 | Major | . | Tsz Wo Nicholas Sze | Hairong Kuang

### OTHER:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-4150 | Include librecordio as part of the release | Blocker | build | Koji Noguchi | Giridharan Kesavan