Package org.apache.flink.state.forst

Class ForStIncrementalCheckpointUtils

  • public class ForStIncrementalCheckpointUtils
extends Object
    Utils for RocksDB Incremental Checkpoint.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  ForStIncrementalCheckpointUtils.RangeCheckResult
      Helper class that represents the result of a range check of the actual keys in a RocksDB instance against the proclaimed key-group range of the instance.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static boolean beforeThePrefixBytes​(byte[] bytes, byte[] prefixBytes)
      check whether the bytes is before prefixBytes in the character order.
      static ForStIncrementalCheckpointUtils.RangeCheckResult checkSstDataAgainstKeyGroupRange​(org.forstdb.RocksDB db, int keyGroupPrefixBytes, org.apache.flink.runtime.state.KeyGroupRange dbExpectedKeyGroupRange)
      Checks data in the SST files of the given DB for keys that exceed either the lower and upper bound of the proclaimed key-groups range of the DB.
      static void clipDBWithKeyGroupRange​(org.forstdb.RocksDB db, List<org.forstdb.ColumnFamilyHandle> columnFamilyHandles, org.apache.flink.runtime.state.KeyGroupRange targetKeyGroupRange, org.apache.flink.runtime.state.KeyGroupRange currentKeyGroupRange, int keyGroupPrefixBytes, boolean useDeleteFilesInRange)
      The method to clip the db instance according to the target key group range using the RocksDB.delete(ColumnFamilyHandle, byte[]).
      static <T extends org.apache.flink.runtime.state.KeyedStateHandle>
      int      		 findTheBestStateHandleForInitial​(List<T> restoreStateHandles, org.apache.flink.runtime.state.KeyGroupRange targetKeyGroupRange, double overlapFractionThreshold)
      Choose the best state handle according to the stateHandleEvaluator(KeyedStateHandle, KeyGroupRange, double) to init the initial db from the given lists and returns its index.

    • Constructor Detail

      • ForStIncrementalCheckpointUtils

        public ForStIncrementalCheckpointUtils()

    • Method Detail

      • clipDBWithKeyGroupRange

        public static void clipDBWithKeyGroupRange​(@Nonnull
                                           org.forstdb.RocksDB db,
                                           @Nonnull
                                           List<org.forstdb.ColumnFamilyHandle> columnFamilyHandles,
                                           @Nonnull
                                           org.apache.flink.runtime.state.KeyGroupRange targetKeyGroupRange,
                                           @Nonnull
                                           org.apache.flink.runtime.state.KeyGroupRange currentKeyGroupRange,
                                           @Nonnegative
                                           int keyGroupPrefixBytes,
                                           boolean useDeleteFilesInRange)
                                    throws org.forstdb.RocksDBException
        The method to clip the db instance according to the target key group range using the RocksDB.delete(ColumnFamilyHandle, byte[]).
        Parameters:
        db - the RocksDB instance to be clipped.
        columnFamilyHandles - the column families in the db instance.
        targetKeyGroupRange - the target key group range.
        currentKeyGroupRange - the key group range of the db instance.
        keyGroupPrefixBytes - Number of bytes required to prefix the key groups.
        useDeleteFilesInRange - whether to call db.deleteFilesInRanges for the deleted ranges.
        Throws:
        org.forstdb.RocksDBException

      • checkSstDataAgainstKeyGroupRange

        public static ForStIncrementalCheckpointUtils.RangeCheckResult checkSstDataAgainstKeyGroupRange​(org.forstdb.RocksDB db,
                                                                                                int keyGroupPrefixBytes,
                                                                                                org.apache.flink.runtime.state.KeyGroupRange dbExpectedKeyGroupRange)
        Checks data in the SST files of the given DB for keys that exceed either the lower and upper bound of the proclaimed key-groups range of the DB.
        Parameters:
        db - the DB to check.
        keyGroupPrefixBytes - the number of bytes used to serialize the key-group prefix of keys in the DB.
        dbExpectedKeyGroupRange - the expected key-groups range of the DB.
        Returns:
        the check result with detailed info about lower and upper bound violations.

      • beforeThePrefixBytes

        public static boolean beforeThePrefixBytes​(@Nonnull
                                           byte[] bytes,
                                           @Nonnull
                                           byte[] prefixBytes)
        check whether the bytes is before prefixBytes in the character order.

      • findTheBestStateHandleForInitial

        public static <T extends org.apache.flink.runtime.state.KeyedStateHandle> int findTheBestStateHandleForInitial​(@Nonnull
                                                                                                               List<T> restoreStateHandles,
                                                                                                               @Nonnull
                                                                                                               org.apache.flink.runtime.state.KeyGroupRange targetKeyGroupRange,
                                                                                                               double overlapFractionThreshold)
        Choose the best state handle according to the stateHandleEvaluator(KeyedStateHandle, KeyGroupRange, double) to init the initial db from the given lists and returns its index.
        Type Parameters:
        T - the generic parameter type of the state handles.
        Parameters:
        restoreStateHandles - The candidate state handles.
        targetKeyGroupRange - The target key group range.
        overlapFractionThreshold - configured threshold for overlap.
        Returns:
        the index of the best candidate handle in the list or -1 if the list was empty.