You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-issues@hadoop.apache.org by "Xiangrui Meng (JIRA)" <ji...@apache.org> on 2014/05/17 20:30:15 UTC

[jira] [Updated] (HADOOP-10614) CBZip2InputStream is not threadsafe

     [ https://issues.apache.org/jira/browse/HADOOP-10614?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Xiangrui Meng updated HADOOP-10614:
-----------------------------------

    Attachment: bzip2-2.diff

Remove line "Instances of this class are not threadsafe." from JavaDoc.

> CBZip2InputStream is not threadsafe
> -----------------------------------
>
>                 Key: HADOOP-10614
>                 URL: https://issues.apache.org/jira/browse/HADOOP-10614
>             Project: Hadoop Common
>          Issue Type: Improvement
>    Affects Versions: 1.2.1, 2.2.0
>            Reporter: Xiangrui Meng
>            Assignee: Xiangrui Meng
>         Attachments: bzip2-2.diff, bzip2.diff
>
>
> Hadoop uses CBZip2InputStream to decode bzip2 files. However, the implementation is not threadsafe. This is not a really problem for Hadoop MapReduce because Hadoop runs each task in a separate JVM. But for other libraries that utilize multithreading and use Hadoop's InputFormat, e.g., Spark, it will cause exceptions like the following:
> {code}
> java.lang.ArrayIndexOutOfBoundsException: 6 org.apache.hadoop.io.compress.bzip2.CBZip2InputStream.recvDecodingTables(CBZip2InputStream.java:729) org.apache.hadoop.io.compress.bzip2.CBZip2InputStream.getAndMoveToFrontDecode(CBZip2InputStream.java:795) org.apache.hadoop.io.compress.bzip2.CBZip2InputStream.initBlock(CBZip2InputStream.java:499) org.apache.hadoop.io.compress.bzip2.CBZip2InputStream.changeStateToProcessABlock(CBZip2InputStream.java:330) org.apache.hadoop.io.compress.bzip2.CBZip2InputStream.read(CBZip2InputStream.java:394) org.apache.hadoop.io.compress.BZip2Codec$BZip2CompressionInputStream.read(BZip2Codec.java:428) java.io.InputStream.read(InputStream.java:101) org.apache.hadoop.util.LineReader.readDefaultLine(LineReader.java:205) org.apache.hadoop.util.LineReader.readLine(LineReader.java:169) org.apache.hadoop.mapred.LineRecordReader.next(LineRecordReader.java:176) org.apache.hadoop.mapred.LineRecordReader.next(LineRecordReader.java:43) org.apache.spark.rdd.HadoopRDD$$anon$1.getNext(HadoopRDD.scala:198) org.apache.spark.rdd.HadoopRDD$$anon$1.getNext(HadoopRDD.scala:181) org.apache.spark.util.NextIterator.hasNext(NextIterator.scala:71) org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:35) scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:327) org.apache.spark.util.Utils$.getIteratorSize(Utils.scala:1000) org.apache.spark.rdd.RDD$$anonfun$count$1.apply(RDD.scala:847) org.apache.spark.rdd.RDD$$anonfun$count$1.apply(RDD.scala:847) org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1077) org.apache.spark.SparkContext$$anonfun$runJob$4.apply(SparkContext.scala:1077) org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:111) org.apache.spark.scheduler.Task.run(Task.scala:51) org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:187) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) java.lang.Thread.run(Thread.java:724)
> {code}



--
This message was sent by Atlassian JIRA
(v6.2#6252)