MapJoinMemoryExhaustionException on MR job

Exception trace is as follows:-

org.apache.hadoop.hive.ql.exec.mapjoin.MapJoinMemoryExhaustionException: 2013-11-20 07:30:48 Processing rows: 1700000 Hashtable size: 1699999 Memory usage: 965243784 percentage: 0.906
at org.apache.hadoop.hive.ql.exec.mapjoin.MapJoinMemoryExhaustionHandler.checkMemoryStatus(MapJoinMemoryExhaustionHandler.java:91)

….

Solution:

set hive.auto.convert.join=false;

before running your query to disable local inmemory joins and force the join to be done as a distributed Map-Reduce phase.

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