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ASF GitHub Bot commented on FLINK-6364: --------------------------------------- Github user StefanRRichter commented on a diff in the pull request: https://github.com/apache/flink/pull/3801#discussion_r114289498 --- Diff: flink-contrib/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBKeyedStateHandle.java --- @@ -0,0 +1,209 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.flink.contrib.streaming.state; + +import org.apache.flink.api.common.JobID; +import org.apache.flink.runtime.state.CompositeStateHandle; +import org.apache.flink.runtime.state.KeyGroupRange; +import org.apache.flink.runtime.state.KeyedStateHandle; +import org.apache.flink.runtime.state.SharedStateHandle; +import org.apache.flink.runtime.state.SharedStateRegistry; +import org.apache.flink.runtime.state.StateUtil; +import org.apache.flink.runtime.state.StreamStateHandle; +import org.apache.flink.util.Preconditions; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.util.Map; +import java.util.Set; + +/** + * The handle to states in incremental snapshots taken by {@link RocksDBKeyedStateBackend} + */ +public class RocksDBKeyedStateHandle implements KeyedStateHandle, CompositeStateHandle { + + private static final Logger LOG = LoggerFactory.getLogger(RocksDBKeyedStateHandle.class); + + private static final long serialVersionUID = -8328808513197388231L; + + private final JobID jobId; + + private final String operatorIdentifier; + + private final KeyGroupRange keyGroupRange; + + private final Set<String> newSstFileNames; + + private final Map<String, StreamStateHandle> sstFiles; + + private final Map<String, StreamStateHandle> miscFiles; + + private final StreamStateHandle metaStateHandle; + + private boolean registered; + + RocksDBKeyedStateHandle( + JobID jobId, + String operatorIdentifier, + KeyGroupRange keyGroupRange, + Set<String> newSstFileNames, + Map<String, StreamStateHandle> sstFiles, + Map<String, StreamStateHandle> miscFiles, + StreamStateHandle metaStateHandle) { + + this.jobId = jobId; + this.operatorIdentifier = operatorIdentifier; + this.keyGroupRange = keyGroupRange; + this.newSstFileNames = newSstFileNames; + this.sstFiles = sstFiles; + this.miscFiles = miscFiles; + this.metaStateHandle = metaStateHandle; + this.registered = false; + } + + @Override + public KeyGroupRange getKeyGroupRange() { + return keyGroupRange; + } + + public Map<String, StreamStateHandle> getSstFiles() { + return sstFiles; + } + + public Map<String, StreamStateHandle> getMiscFiles() { + return miscFiles; + } + + public StreamStateHandle getMetaStateHandle() { + return metaStateHandle; + } + + @Override + public KeyedStateHandle getIntersection(KeyGroupRange keyGroupRange) { + if (this.keyGroupRange.getIntersection(keyGroupRange) != KeyGroupRange.EMPTY_KEY_GROUP_RANGE) { + return this; + } else { + return null; --- End diff -- I wonder if it would make sense to also return something like `KeyedStateHandle.EMPTY` here that has a `KeyGroupRange.EMPTY_KEY_GROUP_RANGE` to avoid the use of `null` and the corresponding checks in other code parts. > Implement incremental checkpointing in RocksDBStateBackend > ---------------------------------------------------------- > > Key: FLINK-6364 > URL: https://issues.apache.org/jira/browse/FLINK-6364 > Project: Flink > Issue Type: Sub-task > Components: State Backends, Checkpointing > Reporter: Xiaogang Shi > Assignee: Xiaogang Shi > > {{RocksDBStateBackend}} is well suited for incremental checkpointing because > RocksDB is base on LSM trees, which record updates in new sst files and all > sst files are immutable. By only materializing those new sst files, we can > significantly improve the performance of checkpointing. -- This message was sent by Atlassian JIRA (v6.3.15#6346)