hadoop-streaming

Importing text file : No Columns to parse from file

99封情书 提交于 2019-12-01 15:00:59
问题 I am trying to take input from sys.stdin. This is a map reducer program for hadoop. Input file is in txt form. Preview of the data set: 196 242 3 881250949 186 302 3 891717742 22 377 1 878887116 244 51 2 880606923 166 346 1 886397596 298 474 4 884182806 115 265 2 881171488 253 465 5 891628467 305 451 3 886324817 6 86 3 883603013 62 257 2 879372434 286 1014 5 879781125 200 222 5 876042340 210 40 3 891035994 224 29 3 888104457 303 785 3 879485318 122 387 5 879270459 194 274 2 879539794 291 1042

DiskErrorException on slave machine - Hadoop multinode

戏子无情 提交于 2019-12-01 14:44:12
I am trying to process XML files from hadoop, i got following error on invoking word-count job on XML files . 13/07/25 12:39:57 INFO mapred.JobClient: Task Id : attempt_201307251234_0001_m_000008_0, Status : FAILED Too many fetch-failures 13/07/25 12:39:58 INFO mapred.JobClient: map 99% reduce 0% 13/07/25 12:39:59 INFO mapred.JobClient: map 100% reduce 0% 13/07/25 12:40:56 INFO mapred.JobClient: Task Id : attempt_201307251234_0001_m_000009_0, Status : FAILED Too many fetch-failures 13/07/25 12:40:58 INFO mapred.JobClient: map 99% reduce 0% 13/07/25 12:40:59 INFO mapred.JobClient: map 100%

DiskErrorException on slave machine - Hadoop multinode

那年仲夏 提交于 2019-12-01 12:48:37
问题 I am trying to process XML files from hadoop, i got following error on invoking word-count job on XML files . 13/07/25 12:39:57 INFO mapred.JobClient: Task Id : attempt_201307251234_0001_m_000008_0, Status : FAILED Too many fetch-failures 13/07/25 12:39:58 INFO mapred.JobClient: map 99% reduce 0% 13/07/25 12:39:59 INFO mapred.JobClient: map 100% reduce 0% 13/07/25 12:40:56 INFO mapred.JobClient: Task Id : attempt_201307251234_0001_m_000009_0, Status : FAILED Too many fetch-failures 13/07/25

hadoop streaming: how to see application logs?

元气小坏坏 提交于 2019-12-01 11:27:11
I can see all hadoop logs on my /usr/local/hadoop/logs path but where can I see application level logs? for example : mapper.py import logging def main(): logging.info("starting map task now") // -- do some task -- // print statement reducer.py import logging def main(): for line in sys.stdin: logging.info("received input to reducer - " + line) // -- do some task -- // print statement Where I can see logging.info or related log statements of my application? I am using Python and using hadoop-streaming Thank you Praveen Sripati Hadoop streaming uses STDIN/STDOUT for passing the key/value pairs

Hadoop streaming mapper byte offset not being generated

血红的双手。 提交于 2019-12-01 11:16:23
I'm running a streaming Hadoop job and the byte offsets are not being generated as output (keys) of the mapper, like I would expect it too. The command: $HADOOP_INSTALL/bin/hadoop \ jar $HADOOP_INSTALL/contrib/streaming/hadoop-streaming-$HADOOP_VERSION.jar \ -D stream.map.input.ignoreKey=false \ -inputformat org.apache.hadoop.mapred.TextInputFormat \ -file ./mapper.py \ -file ./reducer.py \ -mapper ./mapper.py \ -reducer ./reducer.py \ -input $INPUT_DIR \ -output $OUTPUT_DIR \ -cmdenv REGEX=$REGEX My understanding is that TextInputFormat is the default, so I also tried the above command

Hadoop streaming mapper byte offset not being generated

假如想象 提交于 2019-12-01 08:27:52
问题 I'm running a streaming Hadoop job and the byte offsets are not being generated as output (keys) of the mapper, like I would expect it too. The command: $HADOOP_INSTALL/bin/hadoop \ jar $HADOOP_INSTALL/contrib/streaming/hadoop-streaming-$HADOOP_VERSION.jar \ -D stream.map.input.ignoreKey=false \ -inputformat org.apache.hadoop.mapred.TextInputFormat \ -file ./mapper.py \ -file ./reducer.py \ -mapper ./mapper.py \ -reducer ./reducer.py \ -input $INPUT_DIR \ -output $OUTPUT_DIR \ -cmdenv REGEX=

Hadoop Streaming Command Failure with Python Error

只谈情不闲聊 提交于 2019-12-01 08:01:54
I'm a newcomer to Ubuntu, Hadoop and DFS but I've managed to install a single-node hadoop instance on my local ubuntu machine following the directions posted on Michael-Noll.com here: http://www.michael-noll.com/tutorials/running-hadoop-on-ubuntu-linux-single-node-cluster/#copy-local-example-data-to-hdfs http://www.michael-noll.com/tutorials/writing-an-hadoop-mapreduce-program-in-python/ I'm currently stuck on running the basic word count example on Hadoop. I'm not sure if the fact I've been running Hadoop out of my Downloads directory makes too much of a difference, but I've atempted to tweek

How can to get the filename from a streaming mapreduce job in R?

社会主义新天地 提交于 2019-12-01 05:56:14
问题 I am streaming an R mapreduce job and I am need to get the filename. I know that Hadoop sets environment variables for the current job before it starts and I can access env vars in R with Sys.getenv(). I found : Get input file name in streaming hadoop program and Sys.getenv(mapred_job_id) works fine, but it is not what I need. I just need the filename and not the job id or name. I also found: How to get filename when running mapreduce job on EC2? But this isn't helpful either. What is the

How to read hadoop sequential file?

孤者浪人 提交于 2019-12-01 03:42:58
I have a sequential file which is the output of hadoop map-reduce job. In this file data is written in key value pairs ,and value itself is a map. I want to read the value as a MAP object so that i can process it further. Configuration config = new Configuration(); Path path = new Path("D:\\OSP\\sample_data\\data\\part-00000"); SequenceFile.Reader reader = new SequenceFile.Reader(FileSystem.get(config), path, config); WritableComparable key = (WritableComparable) reader.getKeyClass().newInstance(); Writable value = (Writable) reader.getValueClass().newInstance(); long position = reader

how to access and manipulate pdf file's datas in Hadoop?

為{幸葍}努か 提交于 2019-12-01 01:43:53
I want to read the PDF file using hadoop, how it is possible? I only know that hadoop can process only txt files, so is there anyway to parse the PDF files to txt. Give me some suggestion. An easy way would be to create a SequenceFile to contain the PDF files. SequenceFile is a binary file format. You could make each record in the SequenceFile a PDF. To do this you would create a class derived from Writable which would contain the PDF and any metadata that you needed. Then you could use any java PDF library such as PDFBox to manipulate the PDFs. Processing PDF files in Hadoop can be done by