[
https://issues.apache.org/jira/browse/HDFS-1783?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13294951#comment-13294951
]
Lars Hofhansl commented on HDFS-1783:
-------------------------------------
@Ted: The first method is overridden in DistributedFileSystem (to avoid having
to change method signatures in each subclass for FileSystem).
PrimitiveCreate is called from FileContext. There seem to be some general
inconsistencies in FileSystem. For example calling FileSystem.create(...,
APPEND, ...) will not append. FileContext.create(..., APPEND, ...) on the other
hand will do the right thing.
This patch does not affect that. The patch will naturally work with
FileContext.create(..., APPEND, ...) I'll add a few more tests for this.
When I'm back in the US, I'll get some performance numbers (judging from my
micro benchmarks, I'd expect some nice improvements as long as the client's
network-link is not saturated).
> Ability for HDFS client to write replicas in parallel
> -----------------------------------------------------
>
> Key: HDFS-1783
> URL: https://issues.apache.org/jira/browse/HDFS-1783
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: hdfs client
> Reporter: dhruba borthakur
> Assignee: Lars Hofhansl
> Attachments: HDFS-1783-trunk-v2.patch, HDFS-1783-trunk-v3.patch,
> HDFS-1783-trunk-v4.patch, HDFS-1783-trunk-v5.patch, HDFS-1783-trunk.patch
>
>
> The current implementation of HDFS pipelines the writes to the three
> replicas. This introduces some latency for realtime latency sensitive
> applications. An alternate implementation that allows the client to write all
> replicas in parallel gives much better response times to these applications.
--
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
