[KUDU-1237] When compaction generates no output, blocks are leaked

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Public beta
• Fix Version/s: 0.6.0
• Component/s: tablet
• Target Version/s: 0.6.0
• Code Review: http://gerrit.cloudera.org:8080/#/c/1355/
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 29/Oct/15 03:08
• Updated: 29/Feb/16 09:52
• Resolved: 30/Oct/15 01:50

Description

In the case that a compaction generates no output, or in the case that we explicitly flush an empty MRS (as in KUDU-1236), we end up orphaning tiny blocks for each column. Combined with the bug in KUDU-1236, this can cause a fairly rapid leak of blocks – on one server we ended up with upwards of 50,000,000 blocks which were averaging less than 100 bytes each.

Issue Links

• is related to: KUDU-678 An empty delta block is orphaned when flushing or compacting with no edits
• is related to: KUDU-1236 Maintenance manager schedules empty flushes when server is above memory limit