maybe you can use
bin/hadoop jar -libjars ${your-depends-jars} your.mapred.jar args

see details:
http://hadoop.apache.org/core/docs/r0.18.1/api/org/apache/hadoop/mapred/JobShell.html

On Thu, Sep 25, 2008 at 12:26 PM, David Hall <[EMAIL PROTECTED]>wrote:

> On Sun, Sep 21, 2008 at 9:41 PM, David Hall <[EMAIL PROTECTED]>
> wrote:
> > On Sun, Sep 21, 2008 at 9:35 PM, Arun C Murthy <[EMAIL PROTECTED]>
> wrote:
> >>
> >> On Sep 21, 2008, at 2:05 PM, David Hall wrote:
> >>
> >>> (New to this list)
> >>>
> >>> Hi,
> >>>
> >>> My research group is setting up a small (20-node) cluster. All of
> >>> these machines are linked by NFS. We have a fairly entrenched
> >>> codebase/development cycle, and in particular we'd like to be able to
> >>> access user $CLASSPATHs in the forked jvms run by the Map and Reduce
> >>> tasks. However, TaskRunner.java (http://tinyurl.com/4enkg4) seems to
> >>> disallow this by specifying it's own.
> >>>
> >>
> >> Using jars on NFS for too many tasks might hurt if you have thousands of
> >> tasks, causing too much load.
> >>
> >> The better solution might be to use the DistributedCache:
> >>
> http://hadoop.apache.org/core/docs/current/mapred_tutorial.html#DistributedCache
> >>
> >> Specifically:
> >>
> http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/filecache/DistributedCache.html#addArchiveToClassPath(org.apache.hadoop.fs.Path,%20org.apache.hadoop.conf.Configuration)<http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/filecache/DistributedCache.html#addArchiveToClassPath%28org.apache.hadoop.fs.Path,%20org.apache.hadoop.conf.Configuration%29>
> >>
> http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/filecache/DistributedCache.html#addFileToClassPath(org.apache.hadoop.fs.Path,%20org.apache.hadoop.conf.Configuration)<http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/filecache/DistributedCache.html#addFileToClassPath%28org.apache.hadoop.fs.Path,%20org.apache.hadoop.conf.Configuration%29>
> >>
> >> Arun
> >
> > Good point.. I hadn't thought of that, but at the moment we're dealing
> > with barrier-to-adoption rather than efficiency. We'll have to go back
> > to PBS if we can't get users (read: picky phd students) on board. I'd
> > rather avoid that scenario...
> >
> > In the meantime, I think I figured out a hack that I'm going to try.
>
> In case anyone's curious, the hack is to create a jar file with a
> manifest that has the Class-Path field set to all the directories and
> jars you want, and to put that in the lib/ folder of another jar, and
> pass that final jar in as the User Jar to a job.
>
> Works like a charm. :-)
>
> -- David
>
> >
> > Thanks!
> >
> > -- David
> >
> >>
> >>> Is there any easy way to "trick" hadoop into making these visible? If
> >>> not, if I were to submit a patch that would (optionally) add
> >>> $CLASSPATH to the forked jvms' classpath, would it be considered?
> >>>
> >>> Thanks,
> >>> David Hall
> >>
> >>
> >
>

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