[HDFS-3370] HDFS hardlink

• Type: New Feature
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Liyin Tang
• Reporter: Hairong Kuang
• Created: 04/May/12 17:13
• Updated: 14/May/13 16:54

Description

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.

Issue Links

• is required by: HBASE-5940 HBase in-cluster backup based on the HDFS hardlink
• relates to: HDFS-3154 Add a notion of immutable/mutable files