You are viewing a plain text version of this content. The canonical link for it is here.
Posted to mapreduce-user@hadoop.apache.org by 张建伟 <co...@gmail.com> on 2014/03/24 09:49:40 UTC
how does hdfs client write a file .
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?
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
the document is important for new hand,please update it frequently.THX!
Vishnu Viswanath <vi...@gmail.com>于2014年3月24日星期一写道：
> Does that mean that the writes are no longer cached?
>
> Vishnu Viswanath
>
> On 24-Mar-2014, at 15:56, Azuryy Yu <azuryyyu@gmail.com<javascript:_e(%7B%7D,'cvml','azuryyyu@gmail.com');>>
> wrote:
>
> 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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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?
>>>>
>>>
>>>
>>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
the document is important for new hand,please update it frequently.THX!
Vishnu Viswanath <vi...@gmail.com>于2014年3月24日星期一写道：
> Does that mean that the writes are no longer cached?
>
> Vishnu Viswanath
>
> On 24-Mar-2014, at 15:56, Azuryy Yu <azuryyyu@gmail.com<javascript:_e(%7B%7D,'cvml','azuryyyu@gmail.com');>>
> wrote:
>
> 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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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?
>>>>
>>>
>>>
>>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
the document is important for new hand,please update it frequently.THX!
Vishnu Viswanath <vi...@gmail.com>于2014年3月24日星期一写道：
> Does that mean that the writes are no longer cached?
>
> Vishnu Viswanath
>
> On 24-Mar-2014, at 15:56, Azuryy Yu <azuryyyu@gmail.com<javascript:_e(%7B%7D,'cvml','azuryyyu@gmail.com');>>
> wrote:
>
> 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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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?
>>>>
>>>
>>>
>>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
the document is important for new hand,please update it frequently.THX!
Vishnu Viswanath <vi...@gmail.com>于2014年3月24日星期一写道：
> Does that mean that the writes are no longer cached?
>
> Vishnu Viswanath
>
> On 24-Mar-2014, at 15:56, Azuryy Yu <azuryyyu@gmail.com<javascript:_e(%7B%7D,'cvml','azuryyyu@gmail.com');>>
> wrote:
>
> 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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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<javascript:_e(%7B%7D,'cvml','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?
>>>>
>>>
>>>
>>
>
Re: how does hdfs client write a file .
Posted by Vishnu Viswanath <vi...@gmail.com>.
Does that mean that the writes are no longer cached?
Vishnu Viswanath
> On 24-Mar-2014, at 15:56, Azuryy Yu <az...@gmail.com> wrote:
>
> 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 <co...@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 <az...@gmail.com>:
>>
>>> Can you give the URL where you looked at?
>>>
>>>
>>>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Vishnu Viswanath <vi...@gmail.com>.
Does that mean that the writes are no longer cached?
Vishnu Viswanath
> On 24-Mar-2014, at 15:56, Azuryy Yu <az...@gmail.com> wrote:
>
> 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 <co...@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 <az...@gmail.com>:
>>
>>> Can you give the URL where you looked at?
>>>
>>>
>>>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Vishnu Viswanath <vi...@gmail.com>.
Does that mean that the writes are no longer cached?
Vishnu Viswanath
> On 24-Mar-2014, at 15:56, Azuryy Yu <az...@gmail.com> wrote:
>
> 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 <co...@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 <az...@gmail.com>:
>>
>>> Can you give the URL where you looked at?
>>>
>>>
>>>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Vishnu Viswanath <vi...@gmail.com>.
Does that mean that the writes are no longer cached?
Vishnu Viswanath
> On 24-Mar-2014, at 15:56, Azuryy Yu <az...@gmail.com> wrote:
>
> 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 <co...@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 <az...@gmail.com>:
>>
>>> Can you give the URL where you looked at?
>>>
>>>
>>>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
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 <co...@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 <az...@gmail.com>:
>
> Can you give the URL where you looked at?
>>
>>
>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>>
>>
>>
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
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 <co...@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 <az...@gmail.com>:
>
> Can you give the URL where you looked at?
>>
>>
>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>>
>>
>>
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
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 <co...@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 <az...@gmail.com>:
>
> Can you give the URL where you looked at?
>>
>>
>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>>
>>
>>
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
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 <co...@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 <az...@gmail.com>:
>
> Can you give the URL where you looked at?
>>
>>
>> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>>
>>
>>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
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 <az...@gmail.com>:
> Can you give the URL where you looked at?
>
>
> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>
>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
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 <az...@gmail.com>:
> Can you give the URL where you looked at?
>
>
> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>
>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
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 <az...@gmail.com>:
> Can you give the URL where you looked at?
>
>
> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>
>
>
Re: how does hdfs client write a file .
Posted by 张建伟 <co...@gmail.com>.
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 <az...@gmail.com>:
> Can you give the URL where you looked at?
>
>
> On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>>
>
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
Can you give the URL where you looked at?
On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
Can you give the URL where you looked at?
On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
Can you give the URL where you looked at?
On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>
Re: how does hdfs client write a file .
Posted by Azuryy Yu <az...@gmail.com>.
Can you give the URL where you looked at?
On Mon, Mar 24, 2014 at 4:49 PM, 张建伟 <co...@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?
>