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HDFS, mail # user - Is append allowed in HDFS?


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Re: Is append allowed in HDFS?
Harsh J 2012-04-09, 10:53
I'd also like to note that there are some unresolved issues with the
append version in the 1.x (stable) line.

Note that HBase's use of the 0.20-append branch features are limited
to using "sync" calls alone (Described in p68 "Coherency Model",
Chapter 3 (The Hadoop Distributed File System) in Hadoop: The
Definitive Guide, 2nd Edition (O'Reilly)). Not the file-reopening
"append" calls. The latter is what is still with issues in the 1.x
releases today. Using the former is alright if its done in the way
similar to HBase's WAL (HLog) (or for similar needs).

On Mon, Apr 9, 2012 at 3:45 PM, Ioan Eugen Stan <[EMAIL PROTECTED]> wrote:
> 2012/4/7 Florin P <[EMAIL PROTECTED]>:
>> Hello!
>>   Just google it for supporting of append into HDFS files and the result:
>> I'm puzzled. Can someone say: YES you can append in TextFile or SequenceFile
>> or whatever format. If yes, in which version this feature is supported ?
>> Also where can I find a good example of using the API? I know that is a long
>> debate about this subject, but really it is challenge to find on the google
>> the current status of this feature.
>> I look forward for a trust source answer.
>> Thank you,
>>   Regards,
>>    Florin
>
> Hi Florian,
>
> HDFS supports append in Hadoop 1.0.x branch and also 0.22 (a.k.a
> hadoop 2.x branch) and 0.23 (a.k.a hadoop 3.x branch).
>
> [1] http://hbase.apache.org/book/hadoop.html
> [2] http://hbase.apache.org/book/hadoop.html -- search for append in
> release notes
>
> Cheers,
> --
> Ioan Eugen Stan
> http://ieugen.blogspot.com/

--
Harsh J