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https://issues.apache.org/jira/browse/PIG-5288?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Rohini Palaniswamy updated PIG-5288:
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Attachment: PIG-5288-1.patch
> Improve performance of PigTextRawBytesComparator
> ------------------------------------------------
>
> Key: PIG-5288
> URL: https://issues.apache.org/jira/browse/PIG-5288
> Project: Pig
> Issue Type: Improvement
> Reporter: Rohini Palaniswamy
> Assignee: Rohini Palaniswamy
> Fix For: 0.18.0
>
> Attachments: PIG-5288-1.patch
>
>
> Came across this stacktrace for a group by when investigating a different
> performance issue.
> {code}
> "TezChild" #22 daemon prio=5 os_prio=0 tid=0x00007fa935495000 nid=0x7c3e
> runnable [0x00007fa91d354000]
> java.lang.Thread.State: RUNNABLE
> at sun.nio.cs.UTF_8$Decoder.decodeLoop(UTF_8.java:412)
> at java.nio.charset.CharsetDecoder.decode(CharsetDecoder.java:579)
> at java.nio.charset.CharsetDecoder.decode(CharsetDecoder.java:802)
> at org.apache.hadoop.io.Text.decode(Text.java:412)
> at org.apache.hadoop.io.Text.decode(Text.java:389)
> at org.apache.hadoop.io.Text.toString(Text.java:280)
> at
> org.apache.pig.impl.io.NullableText.getValueAsPigType(NullableText.java:46)
> at
> org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigTextRawComparator.compare(PigTextRawComparator.java:95)
> at
> org.apache.tez.runtime.library.common.ValuesIterator.readNextKey(ValuesIterator.java:188)
> at
> org.apache.tez.runtime.library.common.ValuesIterator.access$300(ValuesIterator.java:47)
> at
> org.apache.tez.runtime.library.common.ValuesIterator$1$1.next(ValuesIterator.java:143)
> at
> org.apache.pig.backend.hadoop.executionengine.tez.plan.operator.POShuffleTezLoad.getNextTuple(POShuffleTezLoad.java:218)
> {code}
> Conversion to String and comparing is a wastage (result of extending from
> PigTextRawBytesComparator which is used in sorting).
> PigCharArrayWritableComparator which is the equivalent used in mapreduce does
> not. It directly compares it as a Text.
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