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  1. Jackrabbit Oak
  2. OAK-4412

Lucene hybrid index

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Details

    • New Feature
    • Status: Closed
    • Major
    • Resolution: Fixed
    • None
    • 1.5.11, 1.6.0
    • lucene
    • None

    Description

      When running Oak in a cluster, each write operation is expensive. After performing some stress-tests with a geo-distributed Mongo cluster, we've found out that updating property indexes is a large part of the overall traffic.

      The asynchronous index would be an answer here (as the index update won't be made in the client request thread), but the AEM requires the updates to be visible immediately in order to work properly.

      The idea here is to enhance the existing asynchronous Lucene index with a synchronous, locally-stored counterpart that will persist only the data since the last Lucene background reindexing job.

      The new index can be stored in memory or (if necessary) in MMAPed local files. Once the "main" Lucene index is being updated, the local index will be purged.

      Queries will use an union of results from the lucene and lucene-memory indexes.

      The lucene-memory index, as a local stored entity, will be updated using an observer, so it'll get both local and remote changes.

      The original idea has been suggested by chetanm in the discussion for the OAK-4233.

      Feature Docs
      http://jackrabbit.apache.org/oak/docs/query/indexing.html#nrt-indexing

      Attachments

        1. hybrid-benchmark.sh
          2 kB
          Chetan Mehrotra
        2. hybrid-result-v1.txt
          162 kB
          Chetan Mehrotra
        3. OAK-4412.patch
          87 kB
          Tomek Rękawek
        4. OAK-4412-v1.diff
          196 kB
          Chetan Mehrotra

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              chetanm Chetan Mehrotra
              tomek.rekawek Tomek Rękawek
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                Updated:
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