lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Shai Erera <>
Subject Re: Extending Sort/FieldCache
Date Thu, 27 Aug 2009 03:31:01 GMT
Thanks a lot for the response !

I wanted to avoid two things:
* Writing the logic that invokes cache-refresh upon IndexReader reload.
* Write my own TopFieldCollector which uses this cache.

I guess I don't have any other choice by to write both of them, or try to
make TFC more "customizable" such that someone can pass in his own
FieldCachePQ. I'll start w/ my own version and if possible suggest an
extension to TFC.

Thanks again,

On Tue, Aug 25, 2009 at 8:36 PM, Chris Hostetter

> : I'd like to extend Lucene's FieldCache such that it will read native
> values
>        ...
> : payload value to long, and store it in the cache. The reason I want to
> : extend Lucene's FieldCache is because I'd like Lucene to take care of
> : updating this cache when necessary (such as after reopen for example).
> This
> : will allow me to use Lucene's Sort option more easily.
> this was my motivation when i opened LUCENE-831, but i promptly got bogged
> down with other shit and had to abandon that issue ...
> Miller/Uwe/McCandles seemed like they were making really cool progress
> with it, but (if i remember correctly) it seems to have gotten into some
> sort of quagmire related to reopen and segment merging -- which led to a
> lot of the current segment based sortinging we have now, which makes most
> of that issue obsolete.
> but we still have hte issue of wanting to provide your own caching
> mechanism -- which at the moment has no solution that i know of.
> : I noticed Sort can be extended by providing a CUSTOM SortField, but that
> i think you're only option is to use a custom Sort which uses your own
> private cache of some kind.
> : I didn't find a way though to extend FieldCache, or ExtendedFieldCache
> -->
> : even though both are extendable, I don't find the place where they're
> given
> : as input to TopFieldDocCollector, FieldSortedHitQueue etc. Perhaps I'm
> : missing it?
> you're not missing anything ... a singleton is used, and you can't replace
> the singlton because its' a static on the Interface.
> : BTW, if it interests anyone, perhaps augmenting Lucene's sort w/ reading
> : values from a Payload, or doing a complete payload-based-sort, I can work
> up
> : a patch ...
> I believe that was always one of Busch's goals with the payload stuff, but
> last time i remember hearing about it he was thinking that rather then
> doing it directly with payloads he wants to skip ahead to use column-stride
> fields ... not sure if he had an implementation in mind yet though.
> -Hoss
> ---------------------------------------------------------------------
> To unsubscribe, e-mail:
> For additional commands, e-mail:

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message