[ 
https://issues.apache.org/jira/browse/LUCENE-3056?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13027578#comment-13027578
 ] 

Simon Willnauer commented on LUCENE-3056:
-----------------------------------------

Hey chris,

here are some comments:

* I like that you only have to change BooleanQuery to enable this!! nice!
* Can we rename RewriteState into RewriteContext its just more consistent to 
all the other ctx we pass to query and scorer?
* Can we rename DefaultRewriteState into CachingRewriteContext and make a 
RewriteContext that simply does query.rewrite() that way nothing changes by 
default and we can use a static instance in Query#rewrite(IndexReader) maybe as 
an anonymous inner class in Query?
* Can we move CachingRewriteContext into lucene/src/java/org/apache/lucene/util?

This change somewhat depends on LUCENE-3041 since we might wanna pass that 
RewriteContext on a per segment level right? So maybe we should link those 
issues.


> Support Query Rewriting Caching
> -------------------------------
>
>                 Key: LUCENE-3056
>                 URL: https://issues.apache.org/jira/browse/LUCENE-3056
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Search
>    Affects Versions: 4.0
>            Reporter: Chris Male
>             Fix For: 4.0
>
>         Attachments: LUCENE-3056.patch
>
>
> Out of LUCENE-3041, its become apparent that using a Visitor / Walker isn't 
> right for caching the rewrites of Querys.  Although we still intend to 
> introduce the Query / Walker for advanced query transformations, rewriting 
> still serves a purpose for very specific implementation detail writing.  As 
> such, it can be very expensive.  So I think we should introduce first class 
> support for rewrite caching.  I also feel the key is to make the caching as 
> transparent as possible, to reduce the strain on Query implementors.
> The TermState idea gave me the idea of maybe making a RewriteState / 
> RewriteCache / RewriteInterceptor, which would be consulted for rewritten 
> Querys.  It would then maintain an internal cache that it would check.  If a 
> value wasn't found, it'd then call Query#rewrite, and cache the result.
> By having this external rewrite source, people could 'pre' rewrite Querys if 
> they were particularly expensive but also common.

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: dev-h...@lucene.apache.org

Reply via email to