[ 
https://issues.apache.org/jira/browse/HDFS-6984?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Colin Patrick McCabe updated HDFS-6984:
---------------------------------------
    Summary: In Hadoop 3, make FileStatus serialize itself via protobuf  (was: 
In Hadoop 3, make FileStatus no longer a Writable)

> In Hadoop 3, make FileStatus serialize itself via protobuf
> ----------------------------------------------------------
>
>                 Key: HDFS-6984
>                 URL: https://issues.apache.org/jira/browse/HDFS-6984
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>    Affects Versions: 3.0.0
>            Reporter: Colin Patrick McCabe
>            Assignee: Colin Patrick McCabe
>              Labels: BB2015-05-TBR
>         Attachments: HDFS-6984.001.patch, HDFS-6984.002.patch
>
>
> FileStatus was a Writable in Hadoop 2 and earlier.  Originally, we used this 
> to serialize it and send it over the wire.  But in Hadoop 2 and later, we 
> have the protobuf {{HdfsFileStatusProto}} which serves to serialize this 
> information.  The protobuf form is preferable, since it allows us to add new 
> fields in a backwards-compatible way.  Another issue is that already a lot of 
> subclasses of FileStatus don't override the Writable methods of the 
> superclass, breaking the interface contract that read(status.write) should be 
> equal to the original status.
> In Hadoop 3, we should just make FileStatus no longer a writable so that we 
> don't have to deal with these issues.  It's probably too late to do this in 
> Hadoop 2, since user code may be relying on the ability to use the Writable 
> methods on FileStatus objects there.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to