[HDFS-9802] Selectively save blocks to trash dir during rolling upgrades

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Unassigned
• Reporter: Kihwal Lee
• Created: 12/Feb/16 20:49
• Updated: 24/Aug/17 14:22

Description

Currently datanodes save any invalidated blocks to the trash directory during a rolling upgrade. Compared to the "previous" directory for full upgrade, the trash can grow quickly. This is especially true when blocks are created and then quickly deleted.

Since trash is mainly meant to be defense against faulty new namenode and used for rolling back, saving new blocks in trash does not add much value. If anything, datanodes run out of space quicker.

Issue Links

• relates to: HDFS-12348 disable removing blocks to trash while rolling upgrade