hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Konstantin Shvachko (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HDFS-570) When opening a file for read, make the file length avaliable to client.
Date Thu, 24 Sep 2009 20:56:16 GMT

    [ https://issues.apache.org/jira/browse/HDFS-570?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12759252#action_12759252

Konstantin Shvachko commented on HDFS-570:

# For the last block if it is under construction you should return {{BlockInfoUnderConstruction.getExpectedLocations()}}
rather than those reported by data-nodes. The list of reported nodes may be empty, because
the write has not finished yet, but the bytes should still be readable.
I guess we don't have a test for this condition therefore this was not revealed during your
# Could you please replace the new member {{LocatedBlocks.isLastBlockUnderConstruction}} with
I am planning to replace {{BlockInfoUnderConstruction.isUnderConstruction()}} to {{isComplete()}}.
Thisi is because in current implementation block under-construction means 2 things: that the
state is UNDER_CONSTRUCTION and that the state is not COMPLETE, which is confusing. Sorry
my fault.

It would be really good to have this patch ready tomorrow.

> When opening a file for read, make the file length avaliable to client.
> -----------------------------------------------------------------------
>                 Key: HDFS-570
>                 URL: https://issues.apache.org/jira/browse/HDFS-570
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: hdfs client
>    Affects Versions: Append Branch
>            Reporter: Tsz Wo (Nicholas), SZE
>            Assignee: Tsz Wo (Nicholas), SZE
>             Fix For: Append Branch
>         Attachments: h570_20090828.patch, h570_20090922.patch
> In order to support read consistency, DFSClient needs the file length at the file opening
time.  In the current implmentation, DFSClient obtains the file length at the file opening
time but the length is inaccurate if the file is being written.
> For more details, see Section 4 in the [append design doc|https://issues.apache.org/jira/secure/attachment/12415768/appendDesign2.pdf].

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

View raw message