Class OffHeapH3IndexCreator

  • All Implemented Interfaces:
    Closeable, AutoCloseable, GeoSpatialIndexCreator

    public class OffHeapH3IndexCreator
    extends BaseH3IndexCreator
    H3 index creator that uses off-heap memory.

    The posting lists (map from H3 id to doc ids) are initially stored in a TreeMap, then flushed into a file for every 100,000 entries. After all the documents are added, we read all the posting lists from the file and merge them using a priority queue to calculate the final posting lists.

    Off-heap creator uses less heap memory, but is more expensive on computation and needs flush data to disk which can slow down the creation because of the IO latency. Use off-heap creator in the environment where there is limited heap memory or garbage collection can cause performance issue (e.g. index creation at loading time on Pinot Server).