[PIG-5320] TestCubeOperator#testRollupBasic is flaky on Spark 2.2

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.18.0
• Component/s: spark
• Assignee: Nándor Kollár
• Reporter: Nándor Kollár
• Created: 13/Dec/17 10:00
• Updated: 15/Jan/18 15:12
• Resolved: 15/Jan/18 15:12

Description

TestCubeOperator#testRollupBasic occasionally fails with

org.apache.pig.impl.logicalLayer.FrontendException: ERROR 1002: Unable to store alias c
	at org.apache.pig.PigServer$Graph.registerQuery(PigServer.java:1779)
	at org.apache.pig.PigServer.registerQuery(PigServer.java:708)
	at org.apache.pig.tools.grunt.GruntParser.processPig(GruntParser.java:1110)
	at org.apache.pig.tools.pigscript.parser.PigScriptParser.parse(PigScriptParser.java:512)
	at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:230)
	at org.apache.pig.PigServer.registerScript(PigServer.java:781)
	at org.apache.pig.PigServer.registerScript(PigServer.java:858)
	at org.apache.pig.PigServer.registerScript(PigServer.java:821)
	at org.apache.pig.test.Util.registerMultiLineQuery(Util.java:972)
	at org.apache.pig.test.TestCubeOperator.testRollupBasic(TestCubeOperator.java:124)
Caused by: org.apache.pig.impl.plan.VisitorException: ERROR 0: fail to get the rdds of this spark operator: 
	at org.apache.pig.backend.hadoop.executionengine.spark.JobGraphBuilder.visitSparkOp(JobGraphBuilder.java:115)
	at org.apache.pig.backend.hadoop.executionengine.spark.plan.SparkOperator.visit(SparkOperator.java:140)
	at org.apache.pig.backend.hadoop.executionengine.spark.plan.SparkOperator.visit(SparkOperator.java:37)
	at org.apache.pig.impl.plan.DependencyOrderWalker.walk(DependencyOrderWalker.java:87)
	at org.apache.pig.impl.plan.PlanVisitor.visit(PlanVisitor.java:46)
	at org.apache.pig.backend.hadoop.executionengine.spark.SparkLauncher.launchPig(SparkLauncher.java:237)
	at org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.launchPig(HExecutionEngine.java:293)
	at org.apache.pig.PigServer.launchPlan(PigServer.java:1475)
	at org.apache.pig.PigServer.executeCompiledLogicalPlan(PigServer.java:1460)
	at org.apache.pig.PigServer.execute(PigServer.java:1449)
	at org.apache.pig.PigServer.access$500(PigServer.java:119)
	at org.apache.pig.PigServer$Graph.registerQuery(PigServer.java:1774)
Caused by: java.lang.RuntimeException: Unexpected job execution status RUNNING
	at org.apache.pig.tools.pigstats.spark.SparkStatsUtil.isJobSuccess(SparkStatsUtil.java:138)
	at org.apache.pig.tools.pigstats.spark.SparkPigStats.addJobStats(SparkPigStats.java:75)
	at org.apache.pig.tools.pigstats.spark.SparkStatsUtil.waitForJobAddStats(SparkStatsUtil.java:59)
	at org.apache.pig.backend.hadoop.executionengine.spark.JobGraphBuilder.sparkOperToRDD(JobGraphBuilder.java:225)
	at org.apache.pig.backend.hadoop.executionengine.spark.JobGraphBuilder.visitSparkOp(JobGraphBuilder.java:112)

I think the problem is that in JobStatisticCollector#waitForJobToEnd sparkListener.wait() is not inside a loop, like suggested in wait's javadoc:

     * As in the one argument version, interrupts and spurious wakeups are
     * possible, and this method should always be used in a loop:

Thus due to a spurious wakeup, the wait might pass without a notify getting called.