[ https://issues.apache.org/jira/browse/CASSANDRA-1046?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Jonathan Ellis reassigned CASSANDRA-1046: ----------------------------------------- Assignee: Matthew F. Dennis > optimize Memtable.getSliceIterator > ---------------------------------- > > Key: CASSANDRA-1046 > URL: https://issues.apache.org/jira/browse/CASSANDRA-1046 > Project: Cassandra > Issue Type: Improvement > Reporter: Jonathan Ellis > Assignee: Matthew F. Dennis > Fix For: 0.7 > > > As reported by James Golick, about 30% of the time in a read is spent in > SliceQueryFilter.getMemColumnIterator, virtually all of which is in > ConcurrentSkipListMap$Values.toArrray(). > I wrote on the ML: > Besides the UUID optimization you posted, we should do an audit of > ColumnFamily.getSortedColumns and replace with iteration where possible (in > this case, we'd be left with one copy of most of the columns, but that's > better than two). > We can get rid of the other copy by fixing the logic in > Memtable.getSliceIterator, which says "copy all the columns, so we can do a > binary search on them to find where to start," but since columns are natively > in sorted order we could just use an iterator and a while loo -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.