Apache Tez was designed as a low-latency, DAG-based execution engine for Hadoop. It replaced many of the heavyweight MapReduce patterns used by early Hive deployments with more efficient execution graphs, reusing containers and avoiding unnecessary materialization steps.
In practical terms, switching Hive from MapReduce to Tez often yielded 30–50% faster ETL and reporting jobs on the same hardware, especially for complex multi-stage queries.
What Tez Brought to Hive
- DAG execution: instead of chaining MapReduce jobs, Tez represents the query plan as a directed acyclic graph of tasks.
- Container reuse: tasks are scheduled more efficiently on YARN, reducing startup overhead.
- Better pipelining: intermediate data can be handled with less disk I/O compared to classic MapReduce.
- Improved latency: especially visible in Hive ETL workloads with joins, aggregations and multi-step pipelines.
As distributions matured, Tez became a supported execution engine in certain vendor stacks (e.g. in HDP-era Hive deployments), and users could enable it with a simple configuration change instead of custom builds.
Why Manual Tez + CDH 5.4 Integration Is Now Legacy
When this article was originally written, Cloudera’s CDH 5.4 did not officially support Tez. Getting Tez to run with CDH required a series of manual steps:
- Installing specific versions of Maven, JDK and Protobuf on CentOS 6.x
- Cloning the Tez source code and building a matching release (e.g. Tez 0.7) against the CDH Hadoop version
- Modifying
pom.xmlto usehadoop-2.6.0-cdh5.4.xand Cloudera repositories - Packaging Tez, uploading it to HDFS (e.g.
/apps/tez) and configuringtez-site.xml - Extending the
HADOOP_CLASSPATHand settingTEZ_HOMEandTEZ_CONF_DIR - Switching Hive to Tez via
set hive.execution.engine=tez;
These steps were valuable at the time for experimentation, and our own tests showed significant performance improvements on CDH 5.4 clusters. However, this approach:
- Is tightly coupled to an end-of-life distribution (CDH 5.x)
- Depends on outdated toolchains and library versions
- Is not supported by Cloudera and should not be used in modern environments
Modern Perspective: Tez vs. Other Engines
Today, most new data platforms and lakehouse environments use engines such as:
- Spark SQL
- Trino / Presto
- Hive LLAP in legacy deployments
Tez still appears in some long-lived clusters and as an execution option for certain Hive stacks, but the pattern of compiling Tez against a vendor distribution by hand is now a legacy workaround. For any modern deployment:
- Use vendor-supported engines and integration points.
- Avoid building Tez manually against old Hadoop versions.
- Plan migrations off EOL distributions such as CDH 5.x.
Historical Notes
Originally, the environment for our Tez-on-CDH experiments was:
- CDH 5.4 on CentOS 6.7
- Manually installed Maven 3.2.5 and Oracle JDK 8u40
- Protobuf 2.5.0 built from source or precompiled RPMs
- Tez 0.7.0 compiled with a custom Maven profile targeting CDH Hadoop
These details are kept here purely for historical context, to show what it took to run Tez on an unsupported distribution and why modern, supported integrations are preferable today.
For current Tez installation and configuration details, always refer to the official Apache Tez documentation and the guidance of your Hadoop distribution vendor.
If you need help with distributed systems, backend engineering, or data platforms, check my Services.