[HBASE-15321] Ability to open a HRegion from hdfs snapshot.

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.0.0-alpha-1, 1.5.0, 2.0.0
• Fix Version/s: 1.4.1, 2.0.0-beta-2, 2.0.0
• Release Note: HRegion.openReadOnlyFileSystemHRegion() provides the ability to open HRegion from a read-only hdfs snapshot. Because hdfs snapshots are read-only, no cleanup happens when using this API.
• Assignee: churro morales
• Reporter: churro morales
• Created: 25/Feb/16 00:18
• Updated: 01/Feb/19 20:16
• Resolved: 22/Jan/18 20:42

Description

Now that hdfs snapshots are here, we started to run our mapreduce jobs over hdfs snapshots. The thing is, hdfs snapshots are read-only point-in-time copies of the file system. Thus we had to modify the section of code that initialized the region internals in HRegion. We have to skip cleanup of certain directories if the HRegion is backed by a hdfs snapshot. I have a patch for trunk with some basic tests if folks are interested.