hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "dhruba borthakur (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HDFS-1108) ability to create a file whose newly allocated blocks are automatically persisted immediately
Date Wed, 17 Nov 2010 01:01:19 GMT

    [ https://issues.apache.org/jira/browse/HDFS-1108?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12932747#action_12932747
] 

dhruba borthakur commented on HDFS-1108:
----------------------------------------

> how does namenode handle these blocks during restart, if the block was never written
to the datanode?

>From my understanding, this problem exists in the current trunk too (and is not introduced
by this patch) when an application uses hflush.

> ability to create a file whose newly allocated blocks are automatically persisted immediately
> ---------------------------------------------------------------------------------------------
>
>                 Key: HDFS-1108
>                 URL: https://issues.apache.org/jira/browse/HDFS-1108
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: name-node
>            Reporter: dhruba borthakur
>            Assignee: Dmytro Molkov
>         Attachments: HDFS-1108.patch
>
>
> The current HDFS design says that newly allocated blocks for a file are not persisted
in the NN transaction log when the block is allocated. Instead, a hflush() or a close() on
the file persists the blocks into the transaction log. It would be nice if we can immediately
persist newly allocated blocks (as soon as they are allocated) for specific files.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message