A new execution engine for Hadoop
Hive on MR3
Hive running on top of MR3
MR3 is a new execution engine for Hadoop. Similar in spirit to Tez, it is a new execution engine with simpler design, better performance, and more features. MR3 is ready for production use as it supports all major features such as Kerberos-based security, authentication and authorization, fault-tolerance, and recovery. MR3 is implemented in Scala.
Hive on MR3
Hive, the de facto standard for SQL queries in Hadoop, currently supports three execution engines for its backend -- MapReduce, Tez, and Spark. Now Hive can run on top of MR3 as well. Hive on MR3 generally runs faster than Hive on Tez by virtue of the simple architectual design of MR3. In particular, it yields a higher throughput for concurrent queries by making a better utilization of computing resources. Hive 2 and 3 also support an execution mode called LLAP (Low Latency Analytical Processing) designed for interactive queries. In comparision with Hive with LLAP, Hive on MR3 allows elastic allocation of cluster resources, provides better support for concurrency, and fully implements impersonation.