I'm pretty much new in Python object oriented programming and I have trouble understanding the super() function (new style classes) especially when it comes to multiple... moreI'm pretty much new in Python object oriented programming and I have trouble understanding the super() function (new style classes) especially when it comes to multiple inheritance.
For example if you have something like:
class First(object): def __init__(self): print "first" class Second(object): def __init__(self): print "second" class Third(First, Second): def __init__(self): super(Third, self).__init__() print "that's it"
What I don't get is: will the Third() class inherit both constructor methods? If yes, then which one will be run with super() and why?
And what if you want to run the other one? I know it has something to do with Python method resolution order (MRO). less
I am migrating my application from hadoop 1.0.3 to hadoop 2.2.0 and maven build had hadoop-core marked as dependency. Since hadoop-core is not present for hadoop 2.2.0. I tried... moreI am migrating my application from hadoop 1.0.3 to hadoop 2.2.0 and maven build had hadoop-core marked as dependency. Since hadoop-core is not present for hadoop 2.2.0. I tried replacing it with hadoop-client and hadoop-common but I am still getting this error for ant.filter. Can anybody please suggest which artifact to use?
previous config :
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-core</artifactId>
<version>1.0.3</version>
</dependency>
Error:
Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project event: Compilation failure: Compilation failure:
/opt/teamcity/buildAgent/work/c670ebea1992ec2f/event/src/main/java/com/intel/event/EventContext.java: package org.apache.tools.ant.filters does not exist
I never got a chance to work on Impala. I have just started reading about Impala. But i have one basic question which i am not clear about Impala. Impala has its own demons so it... moreI never got a chance to work on Impala. I have just started reading about Impala. But i have one basic question which i am not clear about Impala. Impala has its own demons so it also has its own execution engine or it works on MapR or other execution engine. Thanks in advance
Hi i can't resolve my problem when running hadoop with start-all.sh
rochdi@127:~$ start-all.sh
/usr/local/hadoop/bin/hadoop-daemon.sh: line 62: [: localhost: integer expression... moreHi i can't resolve my problem when running hadoop with start-all.sh
rochdi@127:~$ start-all.sh
/usr/local/hadoop/bin/hadoop-daemon.sh: line 62: [: localhost: integer expression expected
starting namenode, logging to /usr/local/hadoop/libexec/../logs/hadoop-rochdi-namenode-127.0.0.1
localhost: /usr/local/hadoop/bin/hadoop-daemon.sh: line 62: [: localhost: integer expression expected
localhost: starting datanode, logging to /usr/local/hadoop/libexec/../logs/hadoop-rochdi-datanode-127.0.0.1
localhost: /usr/local/hadoop/bin/hadoop-daemon.sh: line 62: [: localhost: integer expression expected
localhost: starting secondarynamenode, logging to /usr/local/hadoop/libexec/../logs/hadoop-rochdi-secondarynamenode-127.0.0.1
/usr/local/hadoop/bin/hadoop-daemon.sh: line 62: [: localhost: integer expression expected
starting jobtracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-rochdi-jobtracker-127.0.0.1
localhost: /usr/local/hadoop/bin/hadoop-daemon.sh: line 62: [: localhost: integer expression... less
I am installing Hadoop on my laptop. SSH works fine, but I cannot start hadoop.
munichong@GrindPad:~$ ssh localhost
Welcome to Ubuntu 12.10 (GNU/Linux 3.5.0-25-generic... moreI am installing Hadoop on my laptop. SSH works fine, but I cannot start hadoop.
munichong@GrindPad:~$ ssh localhost
Welcome to Ubuntu 12.10 (GNU/Linux 3.5.0-25-generic x86_64)
* Documentation: https://help.ubuntu.com/
0 packages can be updated.
0 updates are security updates.
Last login: Mon Mar 4 00:01:36 2013 from localhost
munichong@GrindPad:~$ /usr/sbin/start-dfs.sh
chown: changing ownership of `/var/log/hadoop/root': Operation not permitted
starting namenode, logging to /var/log/hadoop/root/hadoop-munichong-namenode-GrindPad.out
/usr/sbin/hadoop-daemon.sh: line 136: /var/run/hadoop/hadoop-munichong-namenode.pid: Permission denied
usr/sbin/hadoop-daemon.sh: line 135: /var/log/hadoop/root/hadoop-munichong-namenode-GrindPad.out: Permission denied
head: cannot open `/var/log/hadoop/root/hadoop-munichong-namenode-GrindPad.out' for reading: No such file or directory
localhost: chown: changing ownership of `/var/log/hadoop/root': Operation not permitted
localhost: starting datanode, logging to... less
I have uploaded a Directory to hadoop cluster that is having "," in its name like "MyDir, Name" when I am trying to delete this Directory by using rmr hadoop shell command as... moreI have uploaded a Directory to hadoop cluster that is having "," in its name like "MyDir, Name" when I am trying to delete this Directory by using rmr hadoop shell command as following
hadoop dfs -rmr hdfs://host:port/Navi/MyDir, Name
I'm getting the following messages rmr: cannot remove hdfs://host:port/Navi/MyDir,: No such file or directory. rmr: cannot remove Name: No such file or directory.
However I have successfully deleted other Directories from the same location, using the same command i.e.
hadoop dfs -rmr hdfs://host:port/dir_path
I set up and configured a multi-node Hadoop cluster using this tutorial.
When I type in the start-all.sh command, it shows all the processes initializing properly as... moreI set up and configured a multi-node Hadoop cluster using this tutorial.
When I type in the start-all.sh command, it shows all the processes initializing properly as follows:
starting namenode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-namenode-jawwadtest1.out
jawwadtest1: starting datanode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-datanode-jawwadtest1.out
jawwadtest2: starting datanode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-datanode-jawwadtest2.out
jawwadtest1: starting secondarynamenode, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-secondarynamenode-jawwadtest1.out
starting jobtracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-jobtracker-jawwadtest1.out
jawwadtest1: starting tasktracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-tasktracker-jawwadtest1.out
jawwadtest2: starting tasktracker, logging to /usr/local/hadoop/libexec/../logs/hadoop-root-tasktracker-jawwadtest2.out
I've recently started getting into data analysis and I've learned quite a bit over the last year (at the moment, pretty much exclusively using Python). I feel the next step is to... moreI've recently started getting into data analysis and I've learned quite a bit over the last year (at the moment, pretty much exclusively using Python). I feel the next step is to begin training myself in MapReduce/Hadoop. I have no formal computer science training however and so often don't quite understand the jargon that is used when people write about Hadoop, hence my question here.
What I am hoping for is a top level overview of Hadoop (unless there is something else I should be using?) and perhaps a recommendation for some sort of tutorial/text book.
If, for example, I want to parallelise a neural network which I have written in Python, where would I start? Is there a relatively standard method for implementing Hadoop with an algorithm or is each solution very problem specific?
The Apache wiki page describes Hadoop as "a framework for running applications on large cluster built of commodity hardware". But what does that mean? I've heard the term "Hadoop Cluster" and I know that Hadoop is Java... less
If data reaching millions time computing is large.I want to compute in real time that i don't want to use Mapreduce
How to quickly count number of rows.
In Hadoop when do reduce tasks start? Do they start after a certain percentage (threshold) of mappers complete? If so, is this threshold fixed? What kind of threshold is typically used?
I'm currently configuring hadoop on a server running CentOs. When I run start-dfs.sh or stop-dfs.sh, I get the following error:WARN util.NativeCodeLoader: Unable to load... moreI'm currently configuring hadoop on a server running CentOs. When I run start-dfs.sh or stop-dfs.sh, I get the following error:WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicableI'm running Hadoop 2.2.0.Doing a search online brought up this link: http://balanceandbreath.blogspot.ca/2013/01/utilnativecodeloader-unable-to-load.htmlHowever, the contents of /native/ directory on hadoop 2.x appear to be different so I am not sure what to do.I've also added these two environment variables in hadoop-env.sh:export HADOOP_OPTS="$HADOOP_OPTS -Djava.library.path=/usr/local/hadoop/lib/"export HADOOP_COMMON_LIB_NATIVE_DIR="/usr/local/hadoop/lib/native/" less
I want to setup a hadoop-cluster in pseudo-distributed mode. I managed to perform all the setup-steps, including startuping a Namenode, Datanode, Jobtracker and a Tasktracker on... moreI want to setup a hadoop-cluster in pseudo-distributed mode. I managed to perform all the setup-steps, including startuping a Namenode, Datanode, Jobtracker and a Tasktracker on my machine.
Then I tried to run some exemplary programms and faced the java.net.ConnectException: Connection refused error. I stepped back to the very first steps of running some operations in standalone mode and faced the same problem.
I performed even triple-check of all the installation steps and have no idea how to fix it. (I am new to Hadoop and a beginner Ubuntu user thus I kindly ask you for "taking it into account" if providing any guide or tip).
This is the error output I keep receiving:
hduser@marta-komputer:/usr/local/hadoop$ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.6.0.jar grep input output 'dfs+'
15/02/22 18:23:04 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/02/22 18:23:04 INFO client.RMProxy:... less
