Package 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	Description
RocksDBIncrementalCheckpointUtils()

Method Summary

Modifier and Type	Method	Description
static boolean	beforeThePrefixBytes(byte[] bytes, byte[] prefixBytes)	check whether the bytes is before prefixBytes in the character order.
static <T extends org.apache.flink.runtime.state.KeyedStateHandle> T	chooseTheBestStateHandleForInitial(Collection<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.
static void	clipDBWithKeyGroupRange(org.rocksdb.RocksDB db, List<org.rocksdb.ColumnFamilyHandle> columnFamilyHandles, org.apache.flink.runtime.state.KeyGroupRange targetKeyGroupRange, org.apache.flink.runtime.state.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
                                           org.apache.flink.runtime.state.KeyGroupRange targetKeyGroupRange,
                                           @Nonnull
                                           org.apache.flink.runtime.state.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 <T extends org.apache.flink.runtime.state.KeyedStateHandle> T chooseTheBestStateHandleForInitial(@Nonnull
                                                                                                               Collection<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.

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.