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Marcus Eriksson commented on CASSANDRA-7272: -------------------------------------------- The data in that big sstable generated from a major compaction would "never" be compacted. It would contain old data and would most likely block us from dropping tombstones in the regular minor compactions. This does not help 100% but it is atleast better. > Add "Major" Compaction to LCS > ------------------------------ > > Key: CASSANDRA-7272 > URL: https://issues.apache.org/jira/browse/CASSANDRA-7272 > Project: Cassandra > Issue Type: Improvement > Components: Core > Reporter: T Jake Luciani > Assignee: Marcus Eriksson > Priority: Minor > Labels: compaction > Fix For: 3.0 > > > LCS has a number of minor issues (maybe major depending on your perspective). > LCS is primarily used for wide rows so for instance when you repair data in > LCS you end up with a copy of an entire repaired row in L0. Over time if you > repair you end up with multiple copies of a row in L0 - L5. This can make > predicting disk usage confusing. > Another issue is cleaning up tombstoned data. If a tombstone lives in level > 1 and data for the cell lives in level 5 the data will not be reclaimed from > disk until the tombstone reaches level 5. > I propose we add a "major" compaction for LCS that forces consolidation of > data to level 5 to address these. -- This message was sent by Atlassian JIRA (v6.3.4#6332)