Apache Tez processing of Hive jobs

After migrating to CDP Private Cloud Base, CDP Public Cloud, or Cloudera Data Warehouse (CDW) Public Cloud, you must understand how the Apache Tez execution engine is used to run your Hive workloads.

Apache Tez provides the framework to run a job that creates a graph with vertices and tasks. The entire execution plan is created under this framework. Apache Tez provides the following execution modes:

  • Container mode — Every time you run a Hive query, Tez requests a container from YARN.
  • LLAP mode — Every time you run a Hive query, Tez asks the LLAP daemon for a free thread, and starts running a fragment.
SQL syntax in Hive is the same irrespective of execution mode used in Hive. In CDP Private Cloud Base and CDP Public Cloud, Tez always runs in container mode and is commonly called Hive on Tez. In CDW, Tez always runs in LLAP mode. You can use the query isolation feature if you are running complex ETL workloads.