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Robert Muir commented on LUCENE-6863: ------------------------------------- I think this needs to be a very low number, if its going to be "automatic", like 3%, pure abuse case detection, just like how sparse norms worked. Otherwise, it needs to be a separate format in codecs/ that is explicit opt-in by the user. > Store sparse doc values more efficiently > ---------------------------------------- > > Key: LUCENE-6863 > URL: https://issues.apache.org/jira/browse/LUCENE-6863 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Adrien Grand > Assignee: Adrien Grand > Attachments: LUCENE-6863.patch > > > For both NUMERIC fields and ordinals of SORTED fields, we store data in a > dense way. As a consequence, if you have only 1000 documents out of 1B that > have a value, and 8 bits are required to store those 1000 numbers, we will > not require 1KB of storage, but 1GB. > I suspect this mostly happens in abuse cases, but still it's a pity that we > explode storage requirements. We could try to detect sparsity and compress > accordingly. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org