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Flume, mail # user - Flume bz2 issue while processing by a map reduce job

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Flume bz2 issue while processing by a map reduce job
Jagadish Bihani 2012-10-26, 11:00

I have a very peculiar scenario.

  1. My HDFS sink creates a bz2 file. File is perfectly fine I can
decompress it and
read it. It has 0.2 million records.
2. Now I give that file to map-reduce job (hadoop 1.0.3) and
surprisingly it only
reads first 100 records.
3. I then decompress the same file on local file system and use bzip2
command of
linux to again compress it and copy to HDFS.
4. Now I run the map -reduce job and this time it correctly processes
all the records.

I think flume agent writes compressed data to HDFS file in batches. And
bzip2 codec used by hadoop uses only first part of it.

This way bz2 files generated by Flume, if used directly, can't be
processed by Map reduce job.
Is there any solution to it?

Any inputs about other compression formats?


Flume 1.2.0 (Raw version; downloaded from
Hadoop 1.0.3