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36 discussions - 150 posts

  • I am trying to run Hadoop on a cluster of 3 nodes. The namenode and the jobtracker web UI work. I have the namenode running on node A and job tracker running on node B. Is it true that namenode and ...
    PhantomPhantom
    May 24, 2007 at 10:21 pm
    May 29, 2007 at 8:36 pm
  • I know this question pop up so mant times, but I couldn't find a right answer to my case.... hello everyone, i just started to use hadoop and encountered problem on setting up the single node system: ...
    Yu-yang chenYu-yang chen
    May 23, 2007 at 6:23 pm
    May 25, 2007 at 1:14 am
  • All, We are continually experiencing checksum errors when running some jobs under heavy load (specifically merging segments or crawldbs). I am lost as to whether this is a hardware or software ...
    Dennis KubesDennis Kubes
    May 2, 2007 at 4:35 am
    May 24, 2007 at 11:38 am
  • Hello, It says that Hadoop supports the common file system operations, so I just want to ask if it supports Random Read/Write the file? Waiting for your reply, thanks a lot!
    Wayne LiuWayne Liu
    May 22, 2007 at 12:13 am
    May 22, 2007 at 9:37 pm
  • Hi, There are some steps needed to get Hadoop working on Mac OSX Tiger 10.4.x as single node, here they are: a. use terminal (not the gui) b. get sudo or the root account working on your machine. c. ...
    Peter W.Peter W.
    May 30, 2007 at 7:16 pm
    Jun 1, 2007 at 8:33 pm
  • Hi all, We were trying to setup hadoop in our linux environments. When we tried to use a slow machine as the namenode (some Pentium III machine with 512Mb ram). It seems that it was unable to accept ...
    Cedric HoCedric Ho
    May 11, 2007 at 2:40 am
    May 15, 2007 at 2:51 am
  • Hi, I've been trying to use LzoCodec to write a compressed file: public class LzoTest { public static void main(String[] args) throws Exception { final LzoCodec codec = new LzoCodec(); ...
    Espen Amble KolstadEspen Amble Kolstad
    May 24, 2007 at 1:50 pm
    Jun 1, 2007 at 10:50 am
  • How do I specify the classpath via the JobConf ? In my jobtracker web UI I see a whole slew of ClassNotFoundException's for the WordCount$MapClass. The stack trace is pasted below. But how do I fix ...
    PhantomPhantom
    May 29, 2007 at 8:10 pm
    May 29, 2007 at 10:03 pm
  • I want to setup Hadoop to run on a cluster of 3 nodes. Here is the setup of my hadoop-site.xml file : <configuration <property <name fs.default.name</name <value hdfs:///</value </property <property ...
    Avinash LakshmanAvinash Lakshman
    May 23, 2007 at 9:50 pm
    May 24, 2007 at 6:16 am
  • There is method Configuration.setObject(String name, Object value). I tried values of different classes and found that only Strings are passed normally. Other objects turn out to be null when Mapper ...
    Ilya VishnevskyIlya Vishnevsky
    May 30, 2007 at 1:26 pm
    May 31, 2007 at 2:07 pm
  • Hi, We upgraded our code to nutch 0.9 stable version along with hadoop 0.12.3, which is the latest version of hadoop 0.12. After the upgrade, I am seeing task failures during the reduce phase for ...
    Vishal ShahVishal Shah
    May 22, 2007 at 10:49 am
    May 24, 2007 at 12:30 pm
  • Hi, While I was reading the HDFS docs from the wiki, I bump into this sentence: "There is a plan to support appending-writes to a file in future" I would like to know, if possible, what is the time ...
    Ali SalehiAli Salehi
    May 31, 2007 at 6:46 pm
    Jun 1, 2007 at 4:25 pm
  • hi, If there is a file in the HDFS already, and then I want to write to the file in append mode, how to do this? thanks.
    Wayne LiuWayne Liu
    May 27, 2007 at 3:29 pm
    May 29, 2007 at 7:12 pm
  • I ran the sample against two files one of size 1.5 MB and the other 240MB. The bigger file just craps out. The map jobs do not seem to complete. Here is the output from my run. Could someone please ...
    PhantomPhantom
    May 23, 2007 at 10:27 pm
    May 24, 2007 at 7:17 am
  • Hi, I;m new to hadoop and i downloaded hadoop-0.12.3 from apahce website and installed it to a server with RedHat EL4. I followed the instruction from wiki page: 1. formatted the namenod,. 2. use ...
    Yiqing JinYiqing Jin
    May 11, 2007 at 2:52 am
    May 14, 2007 at 9:00 am
  • hey guys, i've setup hadoop in distributed mode (jobtracker, tasktracker, and hdfs daemons), and observing that the map phase executes really quickly but the reduce phase is really slow. the ...
    MoonwatcherMoonwatcher
    May 3, 2007 at 6:21 pm
    May 5, 2007 at 2:35 pm
  • Hi I am not able to get Hadoop run in a cluster at all. I do not know what I am doing wrong. Here are the files I have in my conf directory. Please advice as to what I need to do. hadoop-site.xml ...
    PhantomPhantom
    May 24, 2007 at 7:41 pm
    May 24, 2007 at 8:17 pm
  • Say you have a complicated function that is being called by a map method, but it produces a lot of information that can be used to produce two types of indices, is it possible to have 2 "map" outputs ...
    Mark MeissonnierMark Meissonnier
    May 22, 2007 at 6:32 pm
    May 22, 2007 at 6:55 pm
  • I'm trying to run the sample RandomWriter task on 6 nodes. DFS runs across the nodes, and I'm able to run the task when I have mapred.job.tracker set to "local." However, when I try to actually use a ...
    Esteban Molina-EstolanoEsteban Molina-Estolano
    May 16, 2007 at 5:47 am
    May 16, 2007 at 7:35 pm
  • Hi. I'm trying to read the crawl_generate sequence file from my Nutch: SequenceFile.Reader reader = new SequenceFile.Reader (fs, genPath, conf); Here is the exception I get when I try to run my code: ...
    Ilya VishnevskyIlya Vishnevsky
    May 15, 2007 at 2:32 pm
    May 16, 2007 at 7:55 am
  • Hi All Is there any heuristic to figuring out as to how many map/reduce tasks I need to be running ? For eg if I am processing a file that is 100GB how many map/reduce tasks do I need to run ? Thanks ...
    Avinash LakshmanAvinash Lakshman
    May 29, 2007 at 11:44 pm
    May 30, 2007 at 12:53 pm
  • Hi, I just want to know if hadoop support APPEND WRITE MODE and how to use it. For example: There is a file such as FILEA in the HDFS already,and now I want to write something append to the FILEA but ...
    Wayne LiuWayne Liu
    May 26, 2007 at 2:30 am
    May 28, 2007 at 1:19 am
  • Hi I am trying to run the Word Count sample against a file that is 1.5GB. I have setup Hadoop to run on a cluster of 3 nodes. However I have a reason to beleive that the map tasks are not being ...
    PhantomPhantom
    May 24, 2007 at 12:46 am
    May 24, 2007 at 4:44 am
  • hi guys, when a file being copied to HDFS, it seems that HDFS always writes the first copy of a block to the data node running on the machine that invoked the copy, and the data nodes for the ...
    Moonwatcher32329Moonwatcher32329
    May 22, 2007 at 11:18 pm
    May 23, 2007 at 12:58 am
  • Hello to all. I'm interested in using Hadoop as a large distributed filesystem. Right now I'm not very interested in the Map/Reduce features. I've been trying to find examples of what would be needed ...
    Cesar DelgadoCesar Delgado
    May 16, 2007 at 4:07 pm
    May 16, 2007 at 8:04 pm
  • Is there a way to redistribute blocks evenly across all DFS nodes. If not I would be happy to program a tool to do so but I would need a little guidance on howto. Dennis Kubes
    Dennis KubesDennis Kubes
    May 16, 2007 at 4:11 pm
    May 16, 2007 at 5:08 pm
  • Hi all, How can I increase the maximum heap space of the child JVM's spawned by the task tracker? (I get 'java.lang.OutOfMemoryError: Java heap space' errors in my map tasks) Thanks! Mathijs Homminga ...
    Mathijs HommingaMathijs Homminga
    May 14, 2007 at 10:59 am
    May 14, 2007 at 11:04 am
  • Hello all I've been doing some scaling experiments on our 13-node Hadoop cluster using the RandomWriter/Sort apps as a benchmark. To start with, I modified the benchmark to just write out 1GB of data ...
    Steve SchlosserSteve Schlosser
    May 9, 2007 at 7:18 pm
    May 9, 2007 at 8:40 pm
  • Hello, I'm currently using version 0.7.2 of Hadoop and there is no way for me to upgrade (it is a school project, and they won't upgrade the cluster until after finals). I've ran into an issue where ...
    Andrew HitchcockAndrew Hitchcock
    May 28, 2007 at 7:15 pm
    May 28, 2007 at 7:15 pm
  • I'm using hadoop (v0.4.0-patched) with nutch (v0.8.1). I have 2 servers, and some odd behavior in task allocation, so somes times one server have all the work and the other do nothing. When I put ...
    CybercoufCybercouf
    May 23, 2007 at 5:07 pm
    May 23, 2007 at 5:07 pm
  • Hi When I run the wordcount example, I get nearly 100% CPU utilization for the Map phase, but the Reduce phase takes forever, never breaking more than 1-2% utilization. Looking at the code, the ...
    Steve SchlosserSteve Schlosser
    May 16, 2007 at 7:34 pm
    May 16, 2007 at 7:34 pm
  • Hi, I don't know if this is the right place to ask for help, but I've been struggling with hadoop configuration for a few days and I'm running out of ideas. I'm trying to run a perl map/reduce using ...
    Mark MeissonnierMark Meissonnier
    May 15, 2007 at 1:45 am
    May 15, 2007 at 1:45 am
  • I am trying to run Hadoop build 2007-05-10_11-01-53 and also tried stable build but both don't work. I am using cygwin and also tried the instructions from here : ...
    Nfs_ nfsNfs_ nfs
    May 14, 2007 at 4:59 pm
    May 14, 2007 at 4:59 pm
  • I try to recompiler WordCount.java file in the same directory as WordCount.class but it doesn't works ! report said something wrong with path, but I cannot figure out ...
    Carson LiaoCarson Liao
    May 10, 2007 at 6:22 pm
    May 10, 2007 at 6:22 pm
  • Hi, my name is Eugene Hung. I work for IBM and have been exploring Hadoop for the past few months along with my colleagues Julian Friedman and Dennis Quan. We have developed the IBM MapReduce Tools ...
    Eugene HungEugene Hung
    May 8, 2007 at 6:42 pm
    May 8, 2007 at 6:42 pm
  • hi, i have the same problem on my server (freebsd 6.2) how to fix it? http://www.rockstarprogrammer.org/post/2007/apr/10/if-you-wrote-code-you-suck/ ...
    DerevoDerevo
    May 1, 2007 at 12:04 am
    May 1, 2007 at 12:04 am
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groupcommon-user @
categorieshadoop
discussions36
posts150
users51
websitehadoop.apache.org...
irc#hadoop

51 users for May 2007

Phantom: 13 posts Dennis Kubes: 10 posts Yu-yang chen: 10 posts Avinash Lakshman: 9 posts Doug Cutting: 8 posts Wayne Liu: 8 posts Mahadev Konar: 6 posts Arun C Murthy: 5 posts Cedric Ho: 5 posts Michael Bieniosek: 5 posts Ilya Vishnevsky: 4 posts Vishal Shah: 4 posts Enis Soztutar: 3 posts Espen Amble Kolstad: 3 posts Esteban Molina-Estolano: 3 posts Hairong Kuang: 3 posts Konstantin Shvachko: 3 posts Mark Meissonnier: 3 posts Moonwatcher32329: 3 posts Owen O'Malley: 3 posts
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