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Rob Audenaerde edited comment on LUCENE-5476 at 3/3/14 12:46 PM: ----------------------------------------------------------------- Quick update: I implemented the single pass on the 'addDoc' method using a fixed interval (which should be the fastest implementation I guess) Exact: 180ms Single Pass (no-clone) Fixed Interval: 38ms. This is an almost 4.75x speed-up. I will compare this later on with a single pass random indexed approach. {quote} Hmm, I don't think the single-pass option would require xorshift.nextInt() on every call? Couldn't you keep a countInBin field in your SampledDocs, increment it on each Docs.addDoc, and when it's == randomIndex, add to the sampled bits and then pick a new randomIndex? This should save a 2nd pass iteration? {quote} Yes I thought of this too. I will update this. I think I prefer the single pass option myself, as I do not need the original bitset and the faster option. was (Author: robau): Quick update: I implemented the single pass on the 'addDoc' method using a fixed interval (which should be the fastest implementation I guess) Exact: 180ms Single Pass (no-clone) Fixed Interval: 38ms. This is a 4.5x speed-up. I will compare this later on with a single pass random indexed approach. {quote} Hmm, I don't think the single-pass option would require xorshift.nextInt() on every call? Couldn't you keep a countInBin field in your SampledDocs, increment it on each Docs.addDoc, and when it's == randomIndex, add to the sampled bits and then pick a new randomIndex? This should save a 2nd pass iteration? {quote} Yes I thought of this too. I will update this. I think I prefer the single pass option myself, as I do not need the original bitset and the faster option. > Facet sampling > -------------- > > Key: LUCENE-5476 > URL: https://issues.apache.org/jira/browse/LUCENE-5476 > Project: Lucene - Core > Issue Type: Improvement > Reporter: Rob Audenaerde > Attachments: LUCENE-5476.patch, LUCENE-5476.patch, > SamplingComparison_SamplingFacetsCollector.java, SamplingFacetsCollector.java > > > With LUCENE-5339 facet sampling disappeared. > When trying to display facet counts on large datasets (>10M documents) > counting facets is rather expensive, as all the hits are collected and > processed. > Sampling greatly reduced this and thus provided a nice speedup. Could it be > brought back? -- This message was sent by Atlassian JIRA (v6.2#6252) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org