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https://issues.apache.org/jira/browse/MAPREDUCE-606?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12787620#action_12787620
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Owen O'Malley commented on MAPREDUCE-606:
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I'd propose that we implement this in terms of the
org.apache.hadoop.streaming.io.InputWriter and OutputReader. A reader/writer
that left the bytes alone, but that quoted the other characters would be great:
{noformat}
newline -> \n
return -> \r
backslash -> \\
tab -> \t
{noformat}
Then it would be easy to get quoted binary into streaming applications.
> Implement a binary input/output format for Streaming
> ----------------------------------------------------
>
> Key: MAPREDUCE-606
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-606
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: contrib/streaming
> Reporter: Arun C Murthy
> Attachments: hadoop-3227.patch
>
>
> Lots of streaming applications process textual data with 1 record per line
> and fields separated by a delimiter. It turns out that there is no point in
> using any of Hadoop's input/output formats since the streaming script/binary
> itself will parse the input and break into records and fields. In such cases
> we should provide users with a binary input/output format which just sends
> 64k (or so) blocks of data directly from HDFS to the streaming application.
> I did something very similar for Pig-Streaming (PIG-94 - BinaryStorage) which
> resulted in 300%+ speedup for scanning (identity mapper & map-only jobs)
> data... the parsing done by input/output formats in these cases were
> pure-overhead.
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