[
https://issues.apache.org/jira/browse/CASSANDRA-6474?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
C. Scott Andreas updated CASSANDRA-6474:
----------------------------------------
Component/s: Compaction
> Compaction strategy based on MinHash
> ------------------------------------
>
> Key: CASSANDRA-6474
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6474
> Project: Cassandra
> Issue Type: New Feature
> Components: Compaction
> Reporter: Yuki Morishita
> Assignee: sankalp kohli
> Priority: Major
> Labels: compaction
> Fix For: 4.x
>
>
> We can consider an SSTable as a set of partition keys, and 'compaction' as
> de-duplication of those partition keys.
> We want to find compaction candidates from SSTables that have as many same
> keys as possible. If we can group similar SSTables based on some measurement,
> we can achieve more efficient compaction.
> One such measurement is [Jaccard
> Distance|http://en.wikipedia.org/wiki/Jaccard_index],
> !http://upload.wikimedia.org/math/1/8/6/186c7f4e83da32e889d606140fae25a0.png!
> which we can estimate using technique called
> [MinHash|http://en.wikipedia.org/wiki/MinHash].
> In Cassandra, we can calculate and store MinHash signature when writing
> SSTable. New compaction strategy uses the signature to find the group of
> similar SSTable for compaction candidates. We can always fall back to STCS
> when such candidates are not exists.
> This is just an idea floating around my head, but before I forget, I dump it
> here. For introduction to this technique, [Chapter 3 of 'Mining of Massive
> Datasets'|http://infolab.stanford.edu/~ullman/mmds/ch3.pdf] is a good start.
--
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
