[CASSANDRA-8739] Don't check for overlap with sstables that have had their start positions moved in LCS

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 2.1.5
• Component/s: Local/Compaction
• Labels: lcs
• Severity: Normal
• Assignee: Marcus Eriksson
• Reporter: Marcus Eriksson

Authors

Marcus Eriksson

Reviewers

Carl Yeksigian

• Created: 04/Feb/15 18:12
• Updated: 16/Apr/19 09:31
• Resolved: 23/Mar/15 08:33

Description

When picking compaction candidates in LCS, we check that we won't cause any overlap in the higher level. Problem is that we compare the files that have had their start positions moved meaning we can cause overlap. We need to also include the tmplink files when checking this.

Note that in 2.1 overlap is not as big problem as earlier, if adding an sstable would cause overlap, we send it back to L0 instead, meaning we do a bit more compaction but we never actually have overlap.