org.apache.flink.contrib.streaming.state

Class RocksDBIncrementalCheckpointUtils

java.lang.Object

org.apache.flink.contrib.streaming.state.RocksDBIncrementalCheckpointUtils

public class RocksDBIncrementalCheckpointUtils
extends Object

Utils for RocksDB Incremental Checkpoint.

Constructor Summary

Constructors

Constructor and Description
RocksDBIncrementalCheckpointUtils()

Method Summary

Modifier and Type	Method and Description
static boolean	beforeThePrefixBytes(byte[] bytes, byte[] prefixBytes) check whether the bytes is before prefixBytes in the character order.
static KeyedStateHandle	chooseTheBestStateHandleForInitial(Collection<KeyedStateHandle> restoreStateHandles, KeyGroupRange targetKeyGroupRange, double overlapFractionThreshold) Choose the best state handle according to the stateHandleEvaluator(KeyedStateHandle, KeyGroupRange, double) to init the initial db.
static void	clipDBWithKeyGroupRange(org.rocksdb.RocksDB db, List<org.rocksdb.ColumnFamilyHandle> columnFamilyHandles, KeyGroupRange targetKeyGroupRange, KeyGroupRange currentKeyGroupRange, int keyGroupPrefixBytes) The method to clip the db instance according to the target key group range using the RocksDB.delete(ColumnFamilyHandle, byte[]).

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RocksDBIncrementalCheckpointUtils

public RocksDBIncrementalCheckpointUtils()

Method Detail

clipDBWithKeyGroupRange

public static void clipDBWithKeyGroupRange(@Nonnull
                                           org.rocksdb.RocksDB db,
                                           @Nonnull
                                           List<org.rocksdb.ColumnFamilyHandle> columnFamilyHandles,
                                           @Nonnull
                                           KeyGroupRange targetKeyGroupRange,
                                           @Nonnull
                                           KeyGroupRange currentKeyGroupRange,
                                           @Nonnegative
                                           int keyGroupPrefixBytes)
                                    throws org.rocksdb.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.

Throws:

org.rocksdb.RocksDBException

beforeThePrefixBytes

public static boolean beforeThePrefixBytes(@Nonnull
                                           byte[] bytes,
                                           @Nonnull
                                           byte[] prefixBytes)

check whether the bytes is before prefixBytes in the character order.

chooseTheBestStateHandleForInitial

@Nullable
public static KeyedStateHandle chooseTheBestStateHandleForInitial(@Nonnull
                                                                            Collection<KeyedStateHandle> restoreStateHandles,
                                                                            @Nonnull
                                                                            KeyGroupRange targetKeyGroupRange,
                                                                            double overlapFractionThreshold)

Choose the best state handle according to the stateHandleEvaluator(KeyedStateHandle, KeyGroupRange, double) to init the initial db.

Parameters:

restoreStateHandles - The candidate state handles.

targetKeyGroupRange - The target key group range.

Returns:

The best candidate or null if no candidate was a good fit.