I'm a total newbie @ Hadoop and and trying to follow an example (a Useful Partitioner Class) on the Hadoop Streaming Wiki, but with my data. So I have data like this:
520460379 1 14067 759015 1142 3 1 8.8 520460380 1 120543 2759354 1142 0 0 0 520460381 3 120543 2759352 1142 0 0 0 520460382 3 12660 679569 1142 0 0 0 520460383 1 120543 2759355 1142 0 0 0 520460384 3 120543 2759353 1142 0 0 0 520460385 1 120575 2759568 1142 0 0 0 520460386 3 120575 2759570 1142 0 0 0 520460387 1 120575 2759569 1142 0 0 0 and I'm trying to run a streaming job that partitions all the keys together based on field 2 and field 3. So for example 1 120543 2759354 and 1 120543 2759355 would go to the same partitioner, and the output key(s) would be something like 1.120543 . I'm trying the following command but get an error: $HADOOP_HOME/bin/hadoop jar $HADOOP_HOME/contrib/streaming/hadoop-0.20.2-streaming.jar \ -D stream.map.output.field.separator=. \ -D stream.num.map.output.key.fields=2 \ -D mapreduce.map.output.key.field.separator=. \ -D mapreduce.partition.keypartitioner.options=-k1,2 \ -D mapreduce.job.reduces=1 \ -input $HOME/temp/foo \ -output dank_phase0 \ -mapper org.apache.hadoop.mapred.lib.IdentityMapper \ -reducer org.apache.hadoop.mapred.lib.IdentityReducer \ -partitioner org.apache.hadoop.mapred.lib.KeyFieldBasedPartitioner 11/11/02 22:45:05 INFO jvm.JvmMetrics: Initializing JVM Metrics with processName=JobTracker, sessionId= 11/11/02 22:45:05 WARN mapred.JobClient: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String). 11/11/02 22:45:05 INFO mapred.FileInputFormat: Total input paths to process : 1 11/11/02 22:45:06 INFO streaming.StreamJob: getLocalDirs(): [/tmp/hadoop-dyoung/mapred/local] 11/11/02 22:45:06 INFO streaming.StreamJob: Running job: job_local_0001 11/11/02 22:45:06 INFO streaming.StreamJob: Job running in-process (local Hadoop) 11/11/02 22:45:06 INFO mapred.FileInputFormat: Total input paths to process : 1 11/11/02 22:45:07 INFO mapred.MapTask: numReduceTasks: 1 11/11/02 22:45:07 INFO mapred.MapTask: io.sort.mb = 200 11/11/02 22:45:07 INFO mapred.MapTask: data buffer = 159383552/199229440 11/11/02 22:45:07 INFO mapred.MapTask: record buffer = 524288/655360 11/11/02 22:45:07 WARN mapred.LocalJobRunner: job_local_0001 java.io.IOException: Type mismatch in key from map: expected org.apache.hadoop.io.Text, recieved org.apache.hadoop.io.LongWritable at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(MapTask.java:845) at org.apache.hadoop.mapred.MapTask$OldOutputCollector.collect(MapTask.java:466) at org.apache.hadoop.mapred.lib.IdentityMapper.map(IdentityMapper.java:40) at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:50) at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:358) at org.apache.hadoop.mapred.MapTask.run(MapTask.java:307) at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:177) 11/11/02 22:45:07 INFO streaming.StreamJob: map 0% reduce 0% 11/11/02 22:45:07 INFO streaming.StreamJob: Job running in-process (local Hadoop) 11/11/02 22:45:07 ERROR streaming.StreamJob: Job not Successful! 11/11/02 22:45:07 INFO streaming.StreamJob: killJob... Streaming Job Failed! I've tried a number of permutations of what's on the Hadoop Wiki, but I'm still having the error. Does anyone have any insight into what I'm doing wrong? Regards, Dan
