[SPARK-13850] TimSort Comparison method violates its general contract

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.6.0
• Fix Version/s: 1.6.2, 2.0.0
• Component/s: Shuffle, Spark Core
• Target Version/s: 1.6.2, 2.0.0
• Assignee: Sameer Agarwal
• Reporter: Sital Kedia
• Created: 14/Mar/16 05:37
• Updated: 17/May/20 18:31
• Resolved: 15/Jun/16 18:57

Description

While running a query which does a group by on a large dataset, the query fails with following stack trace.

Job aborted due to stage failure: Task 4077 in stage 1.3 failed 4 times, most recent failure: Lost task 4077.3 in stage 1.3 (TID 88702, hadoop3030.prn2.facebook.com): java.lang.IllegalArgumentException: Comparison method violates its general contract!
	at org.apache.spark.util.collection.TimSort$SortState.mergeLo(TimSort.java:794)
	at org.apache.spark.util.collection.TimSort$SortState.mergeAt(TimSort.java:525)
	at org.apache.spark.util.collection.TimSort$SortState.mergeCollapse(TimSort.java:453)
	at org.apache.spark.util.collection.TimSort$SortState.access$200(TimSort.java:325)
	at org.apache.spark.util.collection.TimSort.sort(TimSort.java:153)
	at org.apache.spark.util.collection.Sorter.sort(Sorter.scala:37)
	at org.apache.spark.util.collection.unsafe.sort.UnsafeInMemorySorter.getSortedIterator(UnsafeInMemorySorter.java:228)
	at org.apache.spark.util.collection.unsafe.sort.UnsafeExternalSorter.spill(UnsafeExternalSorter.java:186)
	at org.apache.spark.memory.TaskMemoryManager.acquireExecutionMemory(TaskMemoryManager.java:175)
	at org.apache.spark.memory.TaskMemoryManager.allocatePage(TaskMemoryManager.java:249)
	at org.apache.spark.memory.MemoryConsumer.allocatePage(MemoryConsumer.java:112)
	at org.apache.spark.util.collection.unsafe.sort.UnsafeExternalSorter.acquireNewPageIfNecessary(UnsafeExternalSorter.java:318)
	at org.apache.spark.util.collection.unsafe.sort.UnsafeExternalSorter.insertRecord(UnsafeExternalSorter.java:333)
	at org.apache.spark.sql.execution.UnsafeExternalRowSorter.insertRow(UnsafeExternalRowSorter.java:91)
	at org.apache.spark.sql.execution.UnsafeExternalRowSorter.sort(UnsafeExternalRowSorter.java:168)
	at org.apache.spark.sql.execution.Sort$$anonfun$1.apply(Sort.scala:90)
	at org.apache.spark.sql.execution.Sort$$anonfun$1.apply(Sort.scala:64)
	at org.apache.spark.rdd.RDD$$anonfun$mapPartitionsInternal$1$$anonfun$apply$21.apply(RDD.scala:728)
	at org.apache.spark.rdd.RDD$$anonfun$mapPartitionsInternal$1$$anonfun$apply$21.apply(RDD.scala:728)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:38)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:306)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:270)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:38)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:306)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:270)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:38)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:306)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:270)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:38)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:306)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:270)
	at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:38)
	at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:306)
	at org.apache.spark.rdd.RDD.iterator(RDD.scala:270)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:66)
	at org.apache.spark.scheduler.Task.run(Task.scala:89)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:214)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

Please note that the same query used to succeed in Spark 1.5 so it seems like a regression in 1.6.

Issue Links

• is duplicated by: SPARK-8428 TimSort Comparison method violates its general contract with CLUSTER BY
• is related to: SPARK-16070 DataFrame/Parquet issues with primitive arrays
• links to: [Github] Pull Request #13107 (sitalkedia)
• links to: [Github] Pull Request #13336 (sameeragarwal)