http://www.datastax.com/support-forums/tags/mahout Software, Support, and Training for Apache Cassandra en-US Wed, 19 Jun 2013 14:51:37 +0000 http://bbpress.org/?v=1.0.3 q http://www.datastax.com/support-forums/search.php http://www.datastax.com/support-forums/topic/getting-nosuchuserexception-for-mahoutcassandra-database#post-2965 Thu, 12 Jul 2012 07:28:08 +0000 cleophus_p 2965@http://www.datastax.com/support-forums/ <p>Hi All,</p> <p>I am using mahout recommendation with cassandra database. I am getting below error. Initially it was working well with all userids. We did couple of restart tomcat application and we started facing below error. I really need help on this and input will help. Also do we know how to find user in mahout schema using cassandra client. like get Users where rowKey = 10446;<br /> Or get Users where rowKey = "00000000000028ce";</p> <p>Error : --<br /> org.apache.mahout.cf.taste.common.NoSuchUserException: 10186<br /> at </p> <p>org.apache.mahout.cf.taste.impl.model.cassandra.CassandraDataModel$UserPrefArrayRetriever.get(CassandraDataModel.java:387)<br /> at </p> <p>org.apache.mahout.cf.taste.impl.model.cassandra.CassandraDataModel$UserPrefArrayRetriever.get(CassandraDataModel.java:375)<br /> at org.apache.mahout.cf.taste.impl.common.Cache.getAndCacheValue(Cache.java:156)<br /> at org.apache.mahout.cf.taste.impl.common.Cache.get(Cache.java:95)<br /> at </p> <p>org.apache.mahout.cf.taste.impl.model.cassandra.CassandraDataModel.getPreferencesFromUser(CassandraDataModel.java:157)<br /> at </p> <p>org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender.recommend(GenericItemBasedRecommender.java:122)<br /> at com.sharpusa.edge.service.UserSpecificItemsService.getRecommendation(UserSpecificItemsService.java:85) </p> http://www.datastax.com/support-forums/topic/lucenemahout-error-class-overrides-final-method-tokenstream#post-1561 Tue, 10 Apr 2012 14:06:09 +0000 tjake 1561@http://www.datastax.com/support-forums/ <p>This looks to be happening because DSE comes with Lucene/Solr 4.0</p> <p>We can fix this in the next point release so the Solr jars aren't in the classpath when you run hadoop. In the meantime you can move those jars out of the way $DSE_HOME/resources/solr/lib</p> <p>-Jake </p> http://www.datastax.com/support-forums/topic/lucenemahout-error-class-overrides-final-method-tokenstream#post-1544 Fri, 06 Apr 2012 15:33:24 +0000 Anonymous 1544@http://www.datastax.com/support-forums/ <p>Hey, I've been working on getting Mahout to run on top of DataStax Enterprise, but I'm running into issues with Lucene incompatibility.</p> <p>For example, using the Mahout wikipedia bayes example (<a href="https://cwiki.apache.org/MAHOUT/wikipedia-bayes-example.html)" rel="nofollow">https://cwiki.apache.org/MAHOUT/wikipedia-bayes-example.html)</a>, when I execute the following command (step #6 from the example), I end up with errors as shown. (the below command has some *magic* in it, as mahout will assume that a <code>hadoop</code> executable will exist, so I created a <code>hadoop</code> shell script serving as an alias that basically does <code>dse hadoop $@</code>; that's what <code>HADOOP_HOME</code> is pointing to</p> <p><code><br /> sudo env JAVA_HOME=$JAVA_HOME HADOOP_HOME=/home/ubuntu/hadoop HADOOP_CONF_DIR=/etc/dse/hadoop ./mahout wikipediaDataSetCreator -i wikipedia/chunks -o wikipediainput -c /home/ubuntu/mahout/examples/src/test/resources/country.txt<br /> </code></p> <p><code><br /> MAHOUT-JOB: /home/ubuntu/mahout/examples/target/mahout-examples-0.7-SNAPSHOT-job.jar<br /> 12/04/06 14:38:03 WARN driver.MahoutDriver: No wikipediaDataSetCreator.props found on classpath, will use command-line arguments only<br /> 12/04/06 14:38:04 INFO bayes.WikipediaDatasetCreatorDriver: Input: wikipedia/chunks Out: wikipediainput Categories: /home/ubuntu/mahout/examples/src/test/resources/country.txt<br /> 12/04/06 14:38:04 INFO common.HadoopUtil: Deleting wikipediainput<br /> 12/04/06 14:38:05 WARN mapred.JobClient: Use GenericOptionsParser for parsing the arguments. Applications should implement Tool for the same.<br /> 12/04/06 14:38:06 INFO input.FileInputFormat: Total input paths to process : 555<br /> 12/04/06 14:38:07 INFO mapred.JobClient: Running job: job_201204051216_0017<br /> 12/04/06 14:38:08 INFO mapred.JobClient: map 0% reduce 0%<br /> 12/04/06 14:38:26 INFO mapred.JobClient: Task Id : attempt_201204051216_0017_m_000005_0, Status : FAILED<br /> Error: class org.apache.lucene.analysis.ReusableAnalyzerBase overrides final method tokenStream.(Ljava/lang/String;Ljava/io/Reader;)Lorg/apache/lucene/analysis/TokenStream;<br /> 12/04/06 14:38:28 INFO mapred.JobClient: Task Id : attempt_201204051216_0017_m_000002_0, Status : FAILED<br /> Error: class org.apache.lucene.analysis.ReusableAnalyzerBase overrides final method tokenStream.(Ljava/lang/String;Ljava/io/Reader;)Lorg/apache/lucene/analysis/TokenStream;<br /> </code></p> <p>From reading about this error, it appears that Lucene has been patched to make TokenStream final, resulting in the above issues. Mahout itself has an implementation of lucene jars that do not have this problem. I am assuming that the solution lies in getting the dse hadoop to use mahout lucene instead of the lucene it has. Any guidance on that?</p> <p>Cheers,</p> <p>Tristan </p>