You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-user@hadoop.apache.org by ashish pareek <pa...@gmail.com> on 2009/08/11 07:30:59 UTC

Question on file HDFS file system

Hi Everybody,

                   I would like to understand HDFS source code. But basic
question I want to ask is what type of data-structure does HDFS use to store
INode information.  I am interested in knowing what code of HDFS is
responsible with meta-data info of files.
Please can some HDFS-Guru throw some light on this topic and suggest some
way how to understand HDFS source code. :)

Regards,
Ashish

Re: Question on file HDFS file system

Posted by ashish pareek <pa...@gmail.com>.
Hi Everybody,
                   I am already tracing through source code and trying to
figure out things. Any way thanks for all your suggestions.

Regards,
Ashish


On Tue, Aug 11, 2009 at 11:32 PM, Jakob Homan <jh...@yahoo-inc.com> wrote:

> Hey Ashish-
>   In terms of how overall design architecture of HDFS, I would point you to
> the project documentation:
> http://hadoop.apache.org/common/docs/current/hdfs_design.html
> For specific data structures, your first stop should be the INode class and
> its extending classes, located in
> src/java/org/apache/hadoop/hdfs/server/namenode/INode.java (also
> INodeDirectory, INodeFile, etc.)  Looking at how the fsimage file is laid
> out FSImage:LoadFSImage or the OfflineImageViewer classes.
>
> Hope this helps.
>
> -Jakob Homan
> HDFS/Yahoo!
>
>
> ashish pareek wrote:
>
>> Hi Everybody,
>>
>>                   I would like to understand HDFS source code. But basic
>> question I want to ask is what type of data-structure does HDFS use to
>> store
>> INode information.  I am interested in knowing what code of HDFS is
>> responsible with meta-data info of files.
>> Please can some HDFS-Guru throw some light on this topic and suggest some
>> way how to understand HDFS source code. :)
>>
>> Regards,
>> Ashish
>>
>>
>

Re: Question on file HDFS file system

Posted by Jakob Homan <jh...@yahoo-inc.com>.
Hey Ashish-
    In terms of how overall design architecture of HDFS, I would point 
you to the project documentation: 
http://hadoop.apache.org/common/docs/current/hdfs_design.html
For specific data structures, your first stop should be the INode class 
and its extending classes, located in 
src/java/org/apache/hadoop/hdfs/server/namenode/INode.java (also 
INodeDirectory, INodeFile, etc.)  Looking at how the fsimage file is 
laid out FSImage:LoadFSImage or the OfflineImageViewer classes.

Hope this helps.

-Jakob Homan
HDFS/Yahoo!

ashish pareek wrote:
> Hi Everybody,
> 
>                    I would like to understand HDFS source code. But basic
> question I want to ask is what type of data-structure does HDFS use to store
> INode information.  I am interested in knowing what code of HDFS is
> responsible with meta-data info of files.
> Please can some HDFS-Guru throw some light on this topic and suggest some
> way how to understand HDFS source code. :)
> 
> Regards,
> Ashish
>