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Jonathan Ellis commented on CASSANDRA-3234: ------------------------------------------- split OneToOne classes into separate patches and fixed bug in estimated tables calculation > LeveledCompaction has several performance problems > -------------------------------------------------- > > Key: CASSANDRA-3234 > URL: https://issues.apache.org/jira/browse/CASSANDRA-3234 > Project: Cassandra > Issue Type: Bug > Components: Core > Affects Versions: 1.0.0 > Reporter: Jonathan Ellis > Assignee: Jonathan Ellis > Fix For: 1.0.0 > > Attachments: 0001-optimize-single-source-case-for-MergeIterator.txt, > 0002-add-TrivialOneToOne-optimization.txt, > 0003-fix-leveled-BF-size-calculation.txt > > > Two main problems: > - BF size calculation doesn't take into account LCS breaking the output apart > into "bite sized" sstables, so memory use is much higher than predicted > - ManyToMany merging is slow. At least part of this is from running the full > reducer machinery against single input sources, which can be optimized away. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira