[HBASE-16554] Procedure V2 - Recover 'updated' part of WAL tracker if trailer is corrupted.

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0
• Assignee: Apekshit Sharma
• Reporter: Apekshit Sharma
• Created: 02/Sep/16 21:12
• Updated: 17/Jun/22 18:05
• Resolved: 19/Sep/16 19:30

Description

If the last wal was closed cleanly, the global tracker will be the last wal tracker (no rebuild needed)
if the last wal does not have a tracker (corrupted/master-killed). on load() we will rebuild the global tracker.

To compute quickly which files should be deleted, we also want the tracker of each file.
if the wal was closed properly and has a tracker we are good, if not we need to rebuild the tracker for that file.
each file tracker contains a bitmap about what is in the wal (the updated bitmap), which is easy to compute just by reading each entry of the wal.
The 'deleted' bitmap keeps track of the "running procedures" up to that wal, however, it's not required by WAL cleaner, so we don't bother recovering it.

Issue Links

• is related to: HBASE-16094 Procedure v2 - Improve cleaning up of proc wals
• links to: Review Board (master)