[SPARK-3277] LZ4 compression cause the the ExternalSort exception

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.0.2, 1.1.0
• Fix Version/s: 1.1.0
• Component/s: Shuffle, Spark Core
• Assignee: Andrew Or
• Reporter: Zhaowei Huang
• Created: 28/Aug/14 06:27
• Updated: 05/Nov/14 10:45
• Resolved: 29/Aug/14 00:06

Description

I tested the LZ4 compression,and it come up with such problem.(with wordcount)
Also I tested the snappy and LZF,and they were OK.
At last I set the "spark.shuffle.spill" as false to avoid such exeception, but once open this "switch", this error would come.
It seems that if num of the[ words is few, wordcount will go through,but if it is a complex text ,this problem will show
Exeception Info as follow:

java.lang.AssertionError: assertion failed
        at scala.Predef$.assert(Predef.scala:165)
        at org.apache.spark.util.collection.ExternalAppendOnlyMap$DiskMapIterator.<init>(ExternalAppendOnlyMap.scala:416)
        at org.apache.spark.util.collection.ExternalAppendOnlyMap.spill(ExternalAppendOnlyMap.scala:235)
        at org.apache.spark.util.collection.ExternalAppendOnlyMap.insertAll(ExternalAppendOnlyMap.scala:150)
        at org.apache.spark.Aggregator.combineValuesByKey(Aggregator.scala:58)
        at org.apache.spark.shuffle.hash.HashShuffleWriter.write(HashShuffleWriter.scala:55)
        at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:68)
        at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:41)
        at org.apache.spark.scheduler.Task.run(Task.scala:54)
        at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:177)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
        at java.lang.Thread.run(Thread.java:722)

Issue Links

• links to: [Github] Pull Request #2187 (andrewor14)