hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "dhruba borthakur (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-2657) Enhancements to DFSClient to support flushing data at any point in time
Date Fri, 07 Mar 2008 05:52:58 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-2657?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12576047#action_12576047
] 

dhruba borthakur commented on HADOOP-2657:
------------------------------------------

The reason this portion of code is needed is because flushBuffer may invoke writeChunk() for
the last partial cached chunk. This causes currentPacket to change. The portion of code that
you mentioned reverts back the changes to currentPacket.


> Enhancements to DFSClient to support flushing data at any point in time
> -----------------------------------------------------------------------
>
>                 Key: HADOOP-2657
>                 URL: https://issues.apache.org/jira/browse/HADOOP-2657
>             Project: Hadoop Core
>          Issue Type: New Feature
>          Components: dfs
>            Reporter: dhruba borthakur
>            Assignee: dhruba borthakur
>         Attachments: flush.patch, flush2.patch, flush3.patch, flush4.patch, flush5.patch
>
>
> The HDFS Append Design (HADOOP-1700) requires that there be a public API to flush data
written to a HDFS file that can be invoked by an application. This API (popularly referred
to a fflush(OutputStream)) will ensure that data written to the DFSOutputStream is flushed
to datanodes and any required metadata is persisted on Namenode.
> This API has to handle the case when the client decides to flush after writing data that
is not a exact multiple of io.bytes.per.checksum.

-- 
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