[TEZ-248] 0 number of tasks causes Arithmetic exception

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.2.0
• Assignee: Hitesh Shah
• Reporter: Gunther Hagleitner
• Created: 16/Jun/13 23:24
• Updated: 01/Dec/13 20:20
• Resolved: 04/Nov/13 21:15

Description

When hive queries an empty table it will generate a map vertex with "0 tasks." That's because the splitinfo decides that's the right number. When submitting this here's what Tez sez:

2013-06-16 15:42:33,040 DEBUG [AsyncDispatcher event handler] org.apache.tez.dag.app.dag.impl.TaskAttemptImpl: Diagnostics update for attempt_1371421728954_7_1_000001_000000_3: Error: java.lang.ArithmeticException: / by zero
at org.apache.tez.engine.common.shuffle.impl.Shuffle.run(Shuffle.java:122)
at org.apache.tez.engine.lib.input.ShuffledMergedInput.initialize(ShuffledMergedInput.java:67)
at org.apache.tez.mapreduce.processor.reduce.ReduceProcessor.process(ReduceProcessor.java:119)
at org.apache.tez.engine.task.RuntimeTask.run(RuntimeTask.java:79)
at org.apache.tez.mapreduce.task.MRRuntimeTask.run(MRRuntimeTask.java:144)
at org.apache.hadoop.mapred.YarnTezDagChild.runTezTask(YarnTezDagChild.java:334)
at org.apache.hadoop.mapred.YarnTezDagChild.access$000(YarnTezDagChild.java:76)
at org.apache.hadoop.mapred.YarnTezDagChild$2.run(YarnTezDagChild.java:178)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1477)
at org.apache.hadoop.mapred.YarnTezDagChild.main(YarnTezDagChild.java:175)

Issue Links

• duplicates: TEZ-169 Tez should not allow a 0-vertex dag or dags with vertices that have 0 tasks.