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Marcus Eriksson commented on CASSANDRA-14160: --------------------------------------------- hey [~josnyder] the code looks good to me, but, as [~jjirsa] mentioned above, a unit test that makes sure the sstables are returned in the correct order should be added. You also mentioned a that you had not yet benchmarked the change, have you done that? If not, that would also be nice. > maxPurgeableTimestamp should traverse tables in order of minTimestamp > --------------------------------------------------------------------- > > Key: CASSANDRA-14160 > URL: https://issues.apache.org/jira/browse/CASSANDRA-14160 > Project: Cassandra > Issue Type: Bug > Components: Compaction > Reporter: Josh Snyder > Assignee: Josh Snyder > Priority: Major > Labels: performance > Fix For: 4.x > > > In maxPurgeableTimestamp, we iterate over the bloom filters of each > overlapping SSTable. Of the bloom filter hits, we take the SSTable with the > lowest minTimestamp. If we kept the SSTables in sorted order of minTimestamp, > then we could short-circuit the operation at the first bloom filter hit, > reducing cache pressure (or worse, I/O) and CPU time. > I've written (but not yet benchmarked) [some > code|https://github.com/hashbrowncipher/cassandra/commit/29859a4a2e617f6775be49448858bc59fdafab44] > to demonstrate this possibility. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org