Hadoop error in shuffle in fetcher#1

Question

I'm running a parsing job in hadoop, the source is a 11GB map file with about 900,000 binary records each representing an HTML file, the map extract links and write them to the context. I have no reducer written for this job.

• When I run it on smaller files, of about 5GB with about 500,000 records it works ok.
• This is a single machine cluser
• The output has about 100 Million records, TEXT
• It failed after 11 maps tasks out of 200 planned.
• I'm running with Hadoop 0.22.0

I'm getting the following error:

org.apache.hadoop.mapreduce.task.reduce.Shuffle$ShuffleError: error in shuffle in fetcher#1 at org.apache.hadoop.mapreduce.task.reduce.Shuffle.run(Shuffle.java:124) at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:362) at org.apache.hadoop.mapred.Child$4.run(Child.java:223) 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:1153) at org.apache.hadoop.mapred.Child.main(Child.java:217) Caused by: java.lang.OutOfMemoryError: Java heap space at org.apache.hadoop.io.BoundedByteArrayOutputStream.(BoundedByteArrayOutputStream.java:58) at org.apache.hadoop.io.BoundedByteArrayOutputStream.(BoundedByteArrayOutputStream.java:45) at org.apache.hadoop.mapreduce.task.reduce.MapOutput.(MapOutput.java:104) at org.apache.hadoop.mapreduce.task.reduce.MergeManager.unconditionalReserve(MergeManager.java:267)

This is my mapreduce-site.xml:

<configuration>
<property>
  <name>mapred.job.tracker</name>
  <value>Hadp01:8012</value>
  <description>The host and port that the MapReduce job tracker runs
  at.  If "local", then jobs are run in-process as a single map
  and reduce task.
  </description>
</property>
<property>
  <name>mapred.local.dir</name>
  <value>/BigData1/MapReduce,/BigData2/MapReduce</value>
</property>
<property>
  <name>mapred.child.java.opts</name>
  <value>-Xmx1536m</value>
</property>
<property>
        <name>dfs.datanode.max.xcievers</name>
        <value>2048</value>
</property>
<property>
    <name>mapreduce.task.io.sort.mb</name>
    <value>300</value>
</property>
<property>
    <name>io.sort.mb</name>
    <value>300</value>
</property>
<property>
    <name>mapreduce.task.io.sort.factor</name>
    <value>100</value>
</property>
<property>
    <name>io.sort.factor</name>
    <value>100</value>
</property>
<property>
    <name>tasktracker.http.threads</name>
    <value>80</value>
</property>
</configuration>

Anyone has any idea how to fix it? Thank you!

Answer 1

this error caused by mapreduce.reduce.shuffle.memory.limit.percent,by default

mapreduce.reduce.shuffle.memory.limit.percent=0.25

To resolve this problem, I restrict my reduce's shuffle memory usage: hive:

set mapreduce.reduce.shuffle.memory.limit.percent=0.15;

MapReduce:

job.getConfiguration().setStrings("mapreduce.reduce.shuffle.memory.limit.percent", "0.15");

shuffle error solution