[ https://issues.apache.org/jira/browse/HDFS-3370?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13397049#comment-13397049 ]
Sanjay Radia commented on HDFS-3370: ------------------------------------ We should consider two kinds of hard-links: normal and COW. COW-HardLinks are easy since HDFS only allows append and hence one needs to simply record the length. > HDFS hardlink > ------------- > > Key: HDFS-3370 > URL: https://issues.apache.org/jira/browse/HDFS-3370 > Project: Hadoop HDFS > Issue Type: New Feature > Reporter: Hairong Kuang > Assignee: Liyin Tang > Attachments: HDFS-HardLink.pdf > > > We'd like to add a new feature hardlink to HDFS that allows harlinked files > to share data without copying. Currently we will support hardlinking only > closed files, but it could be extended to unclosed files as well. > Among many potential use cases of the feature, the following two are > primarily used in facebook: > 1. This provides a lightweight way for applications like hbase to create a > snapshot; > 2. This also allows an application like Hive to move a table to a different > directory without breaking current running hive queries. -- 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