This is nothing to do with Mahout, but how your Hadoop cluster is configured. I assume you have turned map / reduce output compression and are using the LZO codec.
On Thu, Jul 4, 2013 at 11:06 AM, Sugato Samanta <[email protected]> wrote: > Hello, > > I was trying to execute the recommendation using movie lens data ( > http://www.grouplens.org/node/73). The mahout code is running fine but the > output files are being generated in LZ4 format. Does any one know how to > uncompress this type of file in linux? > > Cloudera version: cdh4.2 > Linux version: Linux 2.6.18-348.6.1.el5 (red hat) > Hadoop version: 2.0.0 > Mahout Version: 0.7 > > Code used: > /usr/bin/mahout recommenditembased --input mahout_recommender/ratings.csv > --output mahout_recommender/output_data --tempDir mahout_recommender/tmp > --usersFile mahout_recommender/users.txt --similarityClassname > SIMILARITY_COOCCURRENCE > > Output files generated: > [root@INFADDAD19 ~]# hdfs dfs -ls mahout_recommender/output_data > Found 32 items > -rw-r--r-- 3 root supergroup 0 2013-07-04 05:39 > mahout_recommender/output_data/_SUCCESS > drwxr-xr-x - root supergroup 0 2013-07-04 05:38 > mahout_recommender/output_data/_logs > -rw-r--r-- 3 root supergroup 9302 2013-07-04 05:38 > mahout_recommender/output_data/*part-r-00000.lz4* > -rw-r--r-- 3 root supergroup 8885 2013-07-04 05:38 > mahout_recommender/output_data/*part-r-00001.lz4* > -rw-r--r-- 3 root supergroup 10033 2013-07-04 05:38 > mahout_recommender/output_data/*part-r-00002.lz4* > > It is generating around 29 LZ4 files but i am specifying only 3 here. Thank > you. > > Regards, > Sugato
