[ https://issues.apache.org/jira/browse/LUCENE-5316?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gilad Barkai updated LUCENE-5316: --------------------------------- Attachment: LUCENE-5316.patch Changes: * Fixed concurrency issues * Moved to an {{int[] getChildren(int ord))}} API which should perform at least as fast as the taxonomy-arrays way. The code is not ready for commit: * Children-map does not support fast reopen (using an older map and only updating with newly added ordinals) * Children-map initialization still uses the taxonomy arrays, so they are not completely removed. Should a benchmark show this change performs better I'll make the extra changes for making it commit-ready. > Taxonomy tree traversing improvement > ------------------------------------ > > Key: LUCENE-5316 > URL: https://issues.apache.org/jira/browse/LUCENE-5316 > Project: Lucene - Core > Issue Type: Improvement > Components: modules/facet > Reporter: Gilad Barkai > Priority: Minor > Attachments: LUCENE-5316.patch, LUCENE-5316.patch, LUCENE-5316.patch, > LUCENE-5316.patch, LUCENE-5316.patch > > > The taxonomy traversing is done today utilizing the > {{ParallelTaxonomyArrays}}. In particular, two taxonomy-size {{int}} arrays > which hold for each ordinal it's (array #1) youngest child and (array #2) > older sibling. > This is a compact way of holding the tree information in memory, but it's not > perfect: > * Large (8 bytes per ordinal in memory) > * Exposes internal implementation > * Utilizing these arrays for tree traversing is not straight forward > * Lose reference locality while traversing (the array is accessed in > increasing only entries, but they may be distant from one another) > * In NRT, a reopen is always (not worst case) done at O(Taxonomy-size) > This issue is about making the traversing more easy, the code more readable, > and open it for future improvements (i.e memory footprint and NRT cost) - > without changing any of the internals. > A later issue(s?) could be opened to address the gaps once this one is done. -- This message was sent by Atlassian JIRA (v6.1#6144) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org