Faster top-k document retrieval using block-max indexes. In Proceedings of the 34th Annual International ACM SIGIR Conference on Research and development in Information Retrieval, pages 993-1002, 2011. ↑の成果は Lucene 8 (2019/3/14 リリース) で実装 参考 https://fosdem.org/2019/schedule/event/apache_lucene_solr_8/attachments/slides/3325/export/events /attachments/apache_lucene_solr_8/slides/3325/SchindlerLucene8Slides.pdf 参考: https://medium.com/@mocobeta/lucene-8-%E3%81%AE-top-k- %E3%82%AF%E3%82%A8%E3%83%AA%E3%83%97%E3%83%AD%E3%82%BB%E3%83%83%E3%82%B7%E3%83%B3%E3 %82%B0%E6%9C%80%E9%81%A9%E5%8C%96-1-%E5%B0%8E%E5%85%A5%E7%B7%A8-5a6387076e8e
for skipInterval = 3: * c (skip level 2) * c c c (skip level 1) * x x x x x x x x x x (skip level 0) * d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d d (posting list) * 3 6 9 12 15 18 21 24 27 30 (df) * * d – document * x - skip data * c - skip data with child pointer
the available memory to Elasticsearch heap, while leaving the other 50% free. It won’t go unused; Lucene will happily gobble up whatever is left over.” 【注意】Java の世界から逸脱している(Java のヒープ外でアロケートされてる)
Balance) • ドキュメント単位でルーティング(デフォルト) – どのシャードに格納するのかは、あなた次第! シャード A, B, C 全部が生存 欠損なしで 検索続行 分散検索: 可用性(Availability) Node Node Node A Shard C Shard B Shard C Shard A Shard B Shard
analytics engine capable of solving a growing number of use cases.” WhitespaceTokenizer “Elasticsearch is a distributed, RESTful search and analytics engine capable of solving a growing number of use cases.”
Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux … TF(Linux) = 14,352 TF(Linux) =2 > これは不都合 注)IDFはどちらも一緒
Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux Linux … TF(Linux) = 14,352 TF(Linux) =2 > これは不都合 注)IDFはどちらも一緒 何が問題?! 単語数! 14,352 > 23