hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Suresh Srinivas (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-3672) Expose disk-location information for blocks to enable better scheduling
Date Mon, 13 Aug 2012 21:04:38 GMT

    [ https://issues.apache.org/jira/browse/HDFS-3672?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13433538#comment-13433538
] 

Suresh Srinivas commented on HDFS-3672:
---------------------------------------

bq. Perhaps Storage(BlockLocation|Id)? Volume(BlockLocation|Id)? I'm not entirely sure of
the end-user terminology here.
DiskBlockLocation could be BlockStorageLocation or just StorageLocation.
DiskId - StorageId seems appropriate here. However it is used for other things in HDFS. Als
you suggested, perhaps VolumeId may be okay.

bq.  Should I just bump the default (say, to 10)? I haven't done any performance testing,
so I don't know if it's a problem.
Only with this feature there will be more RPC calls to datanodes and hence may need more handlers.
Handler is just a thread, so increasing it to 10 should be fine.

@aaron - need server side config as well. That is the only way an admin could control the
accessibility to the feature. One could use exception/support for required method to figure
out if server supports the functionality on client side instead of config.

Please address my previous comment:
bq. Is there a timeline where someone will work on HBase or MapReduce enhancements to use
this capability?

                
> Expose disk-location information for blocks to enable better scheduling
> -----------------------------------------------------------------------
>
>                 Key: HDFS-3672
>                 URL: https://issues.apache.org/jira/browse/HDFS-3672
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>    Affects Versions: 2.0.0-alpha
>            Reporter: Andrew Wang
>            Assignee: Andrew Wang
>         Attachments: design-doc-v1.pdf, design-doc-v2.pdf, hdfs-3672-1.patch, hdfs-3672-2.patch,
hdfs-3672-3.patch, hdfs-3672-4.patch, hdfs-3672-5.patch, hdfs-3672-6.patch, hdfs-3672-7.patch,
hdfs-3672-8.patch
>
>
> Currently, HDFS exposes on which datanodes a block resides, which allows clients to make
scheduling decisions for locality and load balancing. Extending this to also expose on which
disk on a datanode a block resides would enable even better scheduling, on a per-disk rather
than coarse per-datanode basis.
> This API would likely look similar to Filesystem#getFileBlockLocations, but also involve
a series of RPCs to the responsible datanodes to determine disk ids.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

Mime
View raw message