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Introduction

  The Apache Tez project is aimed at building an application framework which allows for a complex directed-acyclic-graph of tasks for processing data. It is currently built atop {{{http://hadoop.apache.org/docs/current/hadoop-yarn/hadoop-yarn-site/YARN.html}Apache Hadoop YARN}}

  The 2 main design themes for Tez are:

  * <<Empowering end users by:>>

    * Expressive dataflow definition APIs

    * Flexible Input-Processor-Output runtime model

    * Data type agnostic

    * Simplifying deployment


  * <<Execution Performance>>

    * Performance gains over Map Reduce

    * Optimal resource management

    * Plan reconfiguration at runtime

    * Dynamic physical data flow decisions

  []

  By allowing projects like Apache Hive and Apache Pig to run a complex DAG of tasks, Tez can be used to process data, that earlier took multiple MR jobs, now in a single Tez job as shown below.

[./images/PigHiveQueryOnMR.png] Flow for a Hive or Pig Query on MapReduce

[./images/PigHiveQueryOnTez.png] Flow for a Hive or Pig Query on Tez

Disclaimer

  Apache Tez is an effort currently undergoing incubation at The Apache Software Foundation (ASF) sponsored by the Apache Incubator PMC.