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How to install Snappy for Hadoop

+1 vote
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I am running on Hadoop 1.0.4 and I would like to use Snappy for map output compression. I am adding the configurations:

configuration.setBoolean("mapred.compress.map.output", true);
 configuration.set("mapred.map.output.compression.codec", "org.apache.hadoop.io.compress.SnappyCodec");

And Ive added libsnappy.so.1 to $HADOOP_HOME/lib/native/Linux-amd64-64/
Still, all map tasks fail with "native snappy library not available". Could anyone elaborate on how to install Snappy for Hadoop ?

posted Jan 1, 2014 by Deepak Dasgupta

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Have  a look at http://hbase.apache.org/book.html#snappy.compression
commented Jan 1, 2014 by Salil Agrawal

1 Answer

+2 votes

Did you build it for your platform? You can do an "ldd" on the .so file to check if the dependent libs are present. Also make sure you placed it in the right directory for your platform (Linux-amd64-64 or Linux-i386-32)

answer Jan 1, 2014 by Ahmed Patel
I did everything mentioned in the link Ted mentioned, and the test actually works, but using Snappy for MapReduce map output compression still fails with "native snappy library not available".
commented Jan 2, 2014 by anonymous
Your natives should be in LD_LIBRARY_PATH or java.library.path for hadoop to pick them up. You can try adding export HADOOP_OPTS=$HADOOP_OPTS -Djava.library.path= to hadoop-env.sh in TTs and clients/gateways and restart TTs and give it another try. The reason its working for Hbase is you are manually pointing HBASE_LIBRARY_PATH to the natives.

My guess is they are in a wrong location.
commented Jan 2, 2014 by anonymous
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