Ted,
Means going the HADOOP_CLASSPATH route, ie. creating a separate
directory for those shared jars and then set it once in the
hadoop-env.sh, I think this will work for me too, I am in the process of
setting a separate CONF_DIR anyways after my recent update - where I
forgot a couple of files to copy them into the new tree.
I was following this:
http://www.mail-archive.com/[EMAIL PROTECTED]/msg02860.html
Which I could not find on the Wiki really, although the above is a
commit. Am I missing something?
Lars
Ted Dunning wrote:
/lib is definitely the way to go.
But adding gobs and gobs of stuff there makes jobs start slowly because you
have to propagate a multi-megabyte blob to lots of worker nodes.
I would consider adding universally used jars to the hadoop class path on
every node, but I would also expect to face configuration management
nightmares (small ones, though) from doing this.
On 1/7/08 11:50 AM, "Lars George" <[EMAIL PROTECTED]> wrote:
Arun,
Ah yes, I see it now in JobClient. OK, then how are the required aux
libs handled? I assume a /lib inside the job jar is the only way to go?
I saw the discussion on the Wiki about adding Hbase permanently to the
HADOOP_CLASSPATH, but then I also have to deploy the Lucene jar files,
Xerces etc. I guess it is better if I add everything non-Hadoop into the
job jar's lib directory?
Thanks again for the help,
Lars
Arun C Murthy wrote:
On Mon, Jan 07, 2008 at 08:24:36AM -0800, Lars George wrote:
Hi,
Maybe someone here can help me with a rather noob question. Where do I
have to put my custom jar to run it as a map/reduce job? Anywhere and
then specifying the HADOOP_CLASSPATH variable in hadoop-env.sh?
Once you have your jar and submit it for your job via the *hadoop jar*
command the framework takes care of distributing the software for nodes on
which your maps/reduces are scheduled:
$ hadoop jar <custom_jar> <custom_args>
The detail is that the framework copies your jar from the submission node to
the HDFS and then copies it onto the execution node.
Does http://lucene.apache.org/hadoop/docs/r0.15.1/mapred_tutorial.html#Usage
help?
Arun
Also, since I am using the Hadoop API already from our server code, it
seems natural to launch jobs from within our code. Are there any issue
with that? I assume I have to copy the jar files first and make them
available as per my question above, but then I am ready to start it from
my own code?
I have read most Wiki entries and while the actual workings are
described quite nicely, I could not find an answer to the questions
above. The demos are already in place and can be started as is without
the need of making them available.
Again, I apologize for being a noobie.
Lars
