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From Azuryy Yu <azury...@gmail.com>
Subject Re: how does hdfs client write a file .
Date Mon, 24 Mar 2014 10:26:36 GMT
Thanks, I think this was deperecated. I'll file a JIRA for this.


On Mon, Mar 24, 2014 at 5:46 PM, 张建伟 <connerlyzhang@gmail.com> wrote:

> http://hadoop.apache.org/docs/r1.2.1/hdfs_design.html
>
>
> Staging
>
> A client request to create a file does not reach the NameNode immediately.
> In fact, initially the HDFS client caches the file data into a temporary
> local file. Application writes are transparently redirected to this
> temporary local file.
>
>
>
>
> 2014-03-24 17:01 GMT+08:00 Azuryy Yu <azuryyyu@gmail.com>:
>
> Can you give the URL where you looked at?
>>
>>
>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <connerlyzhang@gmail.com> wrote:
>>
>>> hi,
>>>
>>> In the apache site,I find a document said :
>>>
>>> "A client request to create a file does not reach the NameNode
>>> immediately. In fact, initially the HDFS client caches the file data into a
>>> temporary local file. Application writes are transparently redirected to
>>> this temporary local file. When the local file accumulates data worth over
>>> one HDFS block size, the client contacts the NameNode. "
>>>
>>> does it still right in 2.2.0 and 1.2.1 version? why write a file like
>>> this?
>>>
>>
>>
>

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