I have written a WebHDFSClient and I do not believe that reusing
connections is enough to noticeably speed up transfers in my case. I did
some tests and on average it took roughly 14 minutes to transfer a 3.6 GB
file to an HDFS on my local network (I tried the same operation using cURL,
with similar results). I tried transferring the exact same file with the
hdfs->dfs->copyFromLocal command, and it took on average 40 seconds. I need
to be able to reliably transfer files that are in the 250 GB - 1TB range,
and I really need the speed afforded by the "direct" transferring method
that libhdfs uses. Does libhdfs work with Hadoop 2.2.0 (if I use it in
Linux)?

--
Kyle Sletmoe

*Urban Robotics Inc.**
*Software Engineer

33 NW First Avenue, Suite 200 | Portland, OR 97209
c: (541) 621-7516 | e: kyle.slet...@urbanrobotics.net

http://www.urbanrobotics.net


On Mon, Oct 28, 2013 at 4:14 PM, Haohui Mai <h...@hortonworks.com> wrote:

> I believe that the WebHDFS API is your best bet for now. The current
> implementation of WebHDFSClient does not reuse the HTTP connections, which
> leads to a large part of the performance penalty.
>
> You might want to implement your own version that reuses HTTP connection to
> see whether it meets your performance requirements.
>
> Thanks,
> Haohui
>
>
> On Mon, Oct 28, 2013 at 3:38 PM, Kyle Sletmoe <
> kyle.slet...@urbanrobotics.net> wrote:
>
> > Now that Hadoop 2.2.0 is Windows compatible, is there going to be work on
> > creating a portable version of libhdfs for C/C++ interaction with HDFS? I
> > know I can use the WebHDFS REST API, but the data transfer rates are
> > abysmally slow compared to the direct interaction via libhdfs.
> >
> > Regards,
> > --
> > Kyle Sletmoe
> >
> > *Urban Robotics Inc.**
> > *Software Engineer
> >
> > 33 NW First Avenue, Suite 200 | Portland, OR 97209
> > c: (541) 621-7516 | e: kyle.slet...@urbanrobotics.net
> >
> > http://www.urbanrobotics.net
> >
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