[jira] [Commented] (LUCENE-10672) Re-evaluate different ways to encode postings

["Michael McCandless (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/LUCENE-10672?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17574668#comment-17574668 ] 

Michael McCandless commented on LUCENE-10672:
---------------------------------------------

+1

Maybe we can also peek at how Vespa and Tantivy do their encoding ... any inspiration there?

The world needs more popular open-search source engines.

> Re-evaluate different ways to encode postings
> ---------------------------------------------
>
>                 Key: LUCENE-10672
>                 URL: https://issues.apache.org/jira/browse/LUCENE-10672
>             Project: Lucene - Core
>          Issue Type: Task
>            Reporter: Adrien Grand
>            Priority: Minor
>
> In Lucene 4, we moved to FOR to encode postings because it woud give better throughput compared to VInts that we had been using until then. This was a time when Lucene would often need to evaluate entire postings lists, and optimizations like BS1 were very important for good performance.
> Nowadays, Lucene performs more dynamic pruning and it's less frequent that Lucene needs to evaluate all hits that match a query. So the performance of {{nextDoc()}} has become a bit less relevant while the performance of {{advance(target)}} has become more relevant.
> I wonder if we should re-evaluate other ways to encode postings that are theoretically better at skipping, such as Elias-Fano coding, since they support skipping directly on the encoded representation instead of requiring decoding a full block of integers where only a couple of them would be relevant.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@lucene.apache.org
For additional commands, e-mail: issues-help@lucene.apache.org