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| |
| Apache Hadoop ${project.version} |
| ================================ |
| |
| Apache Hadoop ${project.version} incorporates a number of significant |
| enhancements over the previous major release line (hadoop-3.2). |
| |
| Overview |
| ======== |
| |
| Users are encouraged to read the full set of release notes. |
| This page provides an overview of the major changes. |
| |
| ARM Support |
| ------------ |
| This is the first release to support ARM architectures. |
| |
| Upgrade protobuf from 2.5.0 to something newer |
| --------------------------------------------- |
| Protobuf upgraded to 3.7.1 as protobuf-2.5.0 reached EOL. |
| |
| Java 11 runtime support |
| ------------------ |
| |
| Java 11 runtime support is completed. |
| |
| Support impersonation for AuthenticationFilter |
| --------------------------------------------- |
| |
| External services or YARN service may need to call into WebHDFS or YARN REST API on behave of the user using web |
| protocols. It would be good to support impersonation mechanism in AuthenticationFilter or similar extensions. |
| |
| |
| s3A Enhancements |
| ------------------ |
| Lots of enhancements to the S3A code including Delegation Token support, better handling of 404 caching, |
| S3guard performance, resilience improvements |
| |
| ABFS Enhancements |
| -------------------- |
| Address issues which surface in the field and tune things which need tuning, add more tests where appropriate. |
| Improve docs, especially troubleshooting. |
| |
| HDFS RBF stabilization |
| -------------------- |
| |
| HDFS Router now supports security. Also contains many bug fixes and improvements. |
| |
| Support non-volatile storage class memory(SCM) in HDFS cache directives . |
| ----------------------------------------------------------------------- |
| |
| Aims to enable storage class memory first in read cache. |
| Although storage class memory has non-volatile characteristics, to keep the same behavior as current read only cache, |
| we don't use its persistent characteristics currently. |
| |
| |
| Application Catalog for YARN applications. |
| ----------------------------------------- |
| |
| application catalog system which provides an editorial and search interface for YARN applications. |
| This improves usability of YARN for manage the life cycle of applications. |
| |
| |
| Incorporate Tencent Cloud COS File System Implementation |
| ------------------------------------------------------- |
| |
| Tencent cloud is top 2 cloud vendors in China market and the object store COS is widely used among China’s cloud users. |
| This task implements a COSN filesytem to support Tencent cloud COS natively in Hadoop. |
| |
| Scheduling of opportunistic containers |
| ------------------------------------- |
| |
| scheduling of opportunistic container through the central RM (YARN-5220), through distributed scheduling (YARN-2877), |
| as well as the scheduling of containers based on actual node utilization (YARN-1011) and the container |
| promotion/demotion (YARN-5085). |
| |
| Getting Started |
| =============== |
| |
| The Hadoop documentation includes the information you need to get started using |
| Hadoop. Begin with the |
| [Single Node Setup](./hadoop-project-dist/hadoop-common/SingleCluster.html) |
| which shows you how to set up a single-node Hadoop installation. |
| Then move on to the |
| [Cluster Setup](./hadoop-project-dist/hadoop-common/ClusterSetup.html) |
| to learn how to set up a multi-node Hadoop installation. |