Package com.hazelcast.query

Interface LocalIndexStats

  • All Superinterfaces:
    com.hazelcast.instance.LocalInstanceStats
    public interface LocalIndexStats
extends com.hazelcast.instance.LocalInstanceStats
    Provides local statistics for an index to be used by MemberState implementations.

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      long getAverageHitLatency()
      Returns the average hit latency (in nanoseconds) for the index.
      double getAverageHitSelectivity()
      Returns the average selectivity of the hits served by the index.
      long getHitCount()
      Returns the total number of hits into the index.
      long getInsertCount()
      Returns the number of insert operations performed on the index.
      long getMemoryCost()
      Returns the memory cost of the index in bytes.
      long getQueryCount()
      Returns the total number of queries served by the index.
      long getRemoveCount()
      Returns the number of remove operations performed on the index.
      long getTotalInsertLatency()
      Returns the total latency (in nanoseconds) of insert operations performed on the index.
      long getTotalRemoveLatency()
      Returns the total latency (in nanoseconds) of remove operations performed on the index.
      long getTotalUpdateLatency()
      Returns the total latency (in nanoseconds) of update operations performed on the index.
      long getUpdateCount()
      Returns the number of update operations performed on the index.

      • Methods inherited from interface com.hazelcast.instance.LocalInstanceStats

        getCreationTime

    • Method Detail

      • getQueryCount

        long getQueryCount()
        Returns the total number of queries served by the index.

        To calculate the index hit rate just divide the returned value by a value returned by LocalMapStats.getQueryCount().

        The returned value may be less than the one returned by getHitCount() since a single query may hit the same index more than once.

      • getHitCount

        long getHitCount()
        Returns the total number of hits into the index.

        The returned value may be greater than the one returned by getQueryCount() since a single query may hit the same index more than once.

      • getAverageHitLatency

        long getAverageHitLatency()
        Returns the average hit latency (in nanoseconds) for the index.

      • getAverageHitSelectivity

        double getAverageHitSelectivity()
        Returns the average selectivity of the hits served by the index.

        The returned value is in the range from 0.0 to 1.0. Values close to 1.0 indicate a high selectivity meaning the index is efficient; values close to 0.0 indicate a low selectivity meaning the index efficiency is approaching an efficiency of a simple full scan.

      • getInsertCount

        long getInsertCount()
        Returns the number of insert operations performed on the index.

      • getTotalInsertLatency

        long getTotalInsertLatency()
        Returns the total latency (in nanoseconds) of insert operations performed on the index.

        To compute the average latency divide the returned value by insert operation count.

      • getUpdateCount

        long getUpdateCount()
        Returns the number of update operations performed on the index.

      • getTotalUpdateLatency

        long getTotalUpdateLatency()
        Returns the total latency (in nanoseconds) of update operations performed on the index.

        To compute the average latency divide the returned value by update operation count.

      • getRemoveCount

        long getRemoveCount()
        Returns the number of remove operations performed on the index.

      • getTotalRemoveLatency

        long getTotalRemoveLatency()
        Returns the total latency (in nanoseconds) of remove operations performed on the index.

        To compute the average latency divide the returned value by remove operation count.

      • getMemoryCost

        long getMemoryCost()
        Returns the memory cost of the index in bytes.

        Currently, for on-heap indexes (OBJECT and BINARY storages), the returned value is just a best-effort approximation and doesn't indicate a precise on-heap memory usage of the index.