[ 
https://issues.apache.org/jira/browse/HADOOP-13843?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Steve Loughran resolved HADOOP-13843.
-------------------------------------
    Resolution: Won't Fix

you'd have to add some lease-marker into the store for this, worry about having 
it expire, etc. best to move to algorithms which don't require atomic 
create-no-overwrite so they will work across all cloud infras

> S3Guard, MetadataStore to support atomic create(path, overwrite=false)
> ----------------------------------------------------------------------
>
>                 Key: HADOOP-13843
>                 URL: https://issues.apache.org/jira/browse/HADOOP-13843
>             Project: Hadoop Common
>          Issue Type: Sub-task
>          Components: fs/s3
>    Affects Versions: 3.0.0-beta1
>            Reporter: Steve Loughran
>            Priority: Major
>
> Support atomically enforced file creation. Current s3a can do a check in 
> create() and fail if there is something there, but a new entry only gets 
> created at the end of the PUT; during the entire interval between that check 
> and the close() of the stream, there's nothing to stop other callers creating 
> an object.
> Proposed: s3afs can do a check + create a 0 byte file at the path; that'd 
> need some {{putNoOverwrite(DirListingMetadata)}} call in MetadataStore, 
> followed by a PUT of an 0-byte file to S3. That will increase cost of file 
> creation, though at least with the MD store, the cost of the initial 
> getFileStatus() check is down.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

---------------------------------------------------------------------
To unsubscribe, e-mail: common-dev-unsubscr...@hadoop.apache.org
For additional commands, e-mail: common-dev-h...@hadoop.apache.org

Reply via email to