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Michael McCandless commented on LUCENE-2335: -------------------------------------------- bq. The sort-first-then-resolve-Strings is what I did in the proof of concept. The speed is that of TermsInfoReader, where it delivers a Term from a given position. If this is too slow for multiple segments, the segment-spanning ordered ordinals-approach could be tried. I fear both approaches are too slow. (This is why we have the per-docXfield String values RAM resident now). bq. As for deprecating stored fields, then I guess there's the issue of spatial locality. Wouldn't moving the bytes into the inverted term index bloat it in a way that makes all searches slower? We're not planning on deprecating stored fields? bq. There's an issue of having multiple terms in the same field for a given document, which also ties into facets. For sorting it must be a single term right? Also, for facets, you have to visit all docs, aggregating, not just the final top N in the queue? Facets are fun to discuss... but let's keep this issue focused on how to optimize the single-segment sorting case with fillFields=false. > optimization: when sorting by field, if index has one segment and field > values are not needed, do not load String[] into field cache > ------------------------------------------------------------------------------------------------------------------------------------ > > Key: LUCENE-2335 > URL: https://issues.apache.org/jira/browse/LUCENE-2335 > Project: Lucene - Java > Issue Type: Improvement > Components: Search > Reporter: Michael McCandless > Priority: Minor > Fix For: 3.1 > > > Spinoff from java-dev thread "Sorting with little memory: A suggestion", > started by Toke Eskildsen. > When sorting by SortField.STRING we currently ask FieldCache for a > StringIndex on that field. > This can consumes tons of RAM, when the values are mostly unique (eg a title > field), as it populates both int[] ords as well as String[] values. > But, if the index is only one segment, and the search sets fillFields=false, > we don't need the String[] values, just the int[] ords. If the app needs to > show the fields it can pull them (for the 1 page) from stored fields. > This can be a potent optimization -- alot of RAM saved -- for optimized > indexes. > When fixing this we must take care to share the int[] ords if some queries do > fillFields=true and some =false... ie, FieldCache will be called twice and it > should share the int[] ords across those invocations. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online. --------------------------------------------------------------------- To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org For additional commands, e-mail: java-dev-h...@lucene.apache.org