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Michael Gibney commented on SOLR-13132: --------------------------------------- Got it, yes, thanks! Merged cleanly, and eliminated (or suppressed as selectively as possible) a handful of warnings unique to this branch (just pushed). Regarding the informal benchmarks, I haven't run them in some time, but it's difficult to compare apples to apples. Full domain skg without sweep over reasonably high-cardinality fields (and without the selective caching introduced by SOLR-13108) currently easily causes filterCache thrashing (really bad); a trivial alternative would be to not consult the filterCache at all, but that carries a different (if more predictable) type of performance hit. So in a sense it feels misleading to run comparison performance benchmarks because non-sweep can't "put it's best foot forward" and a lot of the latency you'd be measuring would be dependent on system-level stuff (filterCache configuration and usage patterns, etc.). I'll try to pull something together that encapsulates these variables in an illustrative way: comparing with filterCache sufficient to hold all terms, filterCache disabled, filterCache thrashing (probably worst-case, and most realistic), and for different cardinality fields and DocSet domains. But ultimately I think the big win is the consistent performance and system-wide benefits that accompany a clean separation from filterCache – and setting up for a bigger win (which I'll mention and then duck!) if/when sweep collection can be integrated with term facet count cache (SOLR-13807). > Improve JSON "terms" facet performance when sorted by relatedness > ------------------------------------------------------------------ > > Key: SOLR-13132 > URL: https://issues.apache.org/jira/browse/SOLR-13132 > Project: Solr > Issue Type: Improvement > Components: Facet Module > Affects Versions: 7.4, master (9.0) > Reporter: Michael Gibney > Priority: Major > Attachments: SOLR-13132-with-cache-01.patch, > SOLR-13132-with-cache.patch, SOLR-13132.patch, SOLR-13132_testSweep.patch > > Time Spent: 1.5h > Remaining Estimate: 0h > > When sorting buckets by {{relatedness}}, JSON "terms" facet must calculate > {{relatedness}} for every term. > The current implementation uses a standard uninverted approach (either > {{docValues}} or {{UnInvertedField}}) to get facet counts over the domain > base docSet, and then uses that initial pass as a pre-filter for a > second-pass, inverted approach of fetching docSets for each relevant term > (i.e., {{count > minCount}}?) and calculating intersection size of those sets > with the domain base docSet. > Over high-cardinality fields, the overhead of per-term docSet creation and > set intersection operations increases request latency to the point where > relatedness sort may not be usable in practice (for my use case, even after > applying the patch for SOLR-13108, for a field with ~220k unique terms per > core, QTime for high-cardinality domain docSets were, e.g.: cardinality > 1816684=9000ms, cardinality 5032902=18000ms). > The attached patch brings the above example QTimes down to a manageable > ~300ms and ~250ms respectively. The approach calculates uninverted facet > counts over domain base, foreground, and background docSets in parallel in a > single pass. This allows us to take advantage of the efficiencies built into > the standard uninverted {{FacetFieldProcessorByArray[DV|UIF]}}), and avoids > the per-term docSet creation and set intersection overhead. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org