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Created on 03-21-201709:46 AM - edited 09-16-202201:39 AM
SYMPTOM
Concurrency issues hit during multi-threaded moveFile issued when processing queries such as "INSERT OVERWRITE TABLE ... SELECT .."
The following pattern is displayed in stack trace:
Loading data to table testdb.test_table from hdfs://xyz/ra_hadoop/.hive-staging_hive_2017-01-31_14-09-52_561_8101886747064006778-4/-ext-10000
ERROR : Failed with exception java.util.ConcurrentModificationException
org.apache.hadoop.hive.ql.metadata.HiveException: java.util.ConcurrentModificationException
at org.apache.hadoop.hive.ql.metadata.Hive.moveFile(Hive.java:2883)
at org.apache.hadoop.hive.ql.metadata.Hive.replaceFiles(Hive.java:3140)
at org.apache.hadoop.hive.ql.metadata.Hive.loadTable(Hive.java:1727)
at org.apache.hadoop.hive.ql.exec.MoveTask.execute(MoveTask.java:353)
at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:160)
at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:89)
at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:1745)
at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:1491)
at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1289)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1156)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1151)
ROOT CAUSE
This issue occurs because of issue described in HIVE-15355.
WORKAROUND
Set the following property at the client side:
set hive.mv.files.thread=0;
Re-run the hive query
Note: The fix for HIVE-15355 is expected to be included in the next major release of HDP.