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From Chandrasekar <chandruseka...@gmail.com>
Subject Re: file metadata
Date Tue, 29 May 2012 10:14:56 GMT
Yeah, the metadata stored was dynamic, the interface exposed to the
client have methods to add additional metadata.

On Tue, May 29, 2012 at 2:50 PM, Petru Dimulescu
<petru.dimulescu@gmail.com> wrote:
> Was the metadata dynamic (map-like)? It looks like your modification
> are pretty useful, despite the fact that some of the comments on
> HDFS-2006 seem to wonder why on earth extended attributes can be used
> for.
>
> On Tue, May 29, 2012 at 5:09 AM, Chandrasekar <chandrusekar47@gmail.com> wrote:
>> Hi,
>>        I did something similar to this a few months back. There are a
>> number of things that you need to change in the name node to
>> accommodate this. You can either provide a special type of INode that
>> extends the existing INodeFile or INodeDirectory or save additional
>> meta data as a part of default inodes created for a file or a
>> directory. Then you need to provide additional methods to the
>> interface exposed to the client by the name node. These methods will
>> be used to access the metadata. You should make sure that the
>> additional metadata is persisted along with other file metadata. This
>> can be done by saving the metadata as a part of the fsimage. Then the
>> metadata will be loaded back to the name node when the system
>> restarts.
>>
>> On Tue, May 29, 2012 at 12:27 AM, Petru Dimulescu
>> <petru.dimulescu@gmail.com> wrote:
>>> Hello,
>>>
>>> If I understand correctly extended attributes are not supported :
>>> https://issues.apache.org/jira/browse/HDFS-2006.
>>>
>>> How would you store small amounts of metadata ("extended attributes") per
>>> HDFS file/directory? Anybody has any experience?
>>>
>>> thanks,
>>> Petru

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