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ASF GitHub Bot commented on FLINK-8715: --------------------------------------- Github user StefanRRichter commented on a diff in the pull request: https://github.com/apache/flink/pull/5885#discussion_r184690567 --- Diff: flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBKeyedStateBackend.java --- @@ -1116,148 +1115,177 @@ private void restoreKeyGroupsShardWithTemporaryHelperInstance( // ------------------------------------------------------------------------ /** - * Creates a column family handle for use with a k/v state. When restoring from a snapshot - * we don't restore the individual k/v states, just the global RocksDB database and the - * list of column families. When a k/v state is first requested we check here whether we - * already have a column family for that and return it or create a new one if it doesn't exist. + * Registers a k/v state information, which includes its state id, type, RocksDB column family handle, and serializers. * - * <p>This also checks whether the {@link StateDescriptor} for a state matches the one - * that we checkpointed, i.e. is already in the map of column families. + * When restoring from a snapshot, we don’t restore the individual k/v states, just the global RocksDB database and + * the list of k/v state information. When a k/v state is first requested we check here whether we + * already have a registered entry for that and return it (after some necessary state compatibility checks) + * or create a new one if it does not exist. */ - @SuppressWarnings("rawtypes, unchecked") - protected <N, S> ColumnFamilyHandle getColumnFamily( - StateDescriptor<?, S> descriptor, TypeSerializer<N> namespaceSerializer) throws IOException, StateMigrationException { + private Tuple2<ColumnFamilyHandle, RegisteredKeyedBackendStateMetaInfo<?, ?>> tryRegisterKvStateInformation( --- End diff -- We could rewrite this as ``` private <N, S> Tuple2<ColumnFamilyHandle, RegisteredKeyedBackendStateMetaInfo<N, S>> tryRegisterKvStateInformation( StateDescriptor<?, S> stateDesc, TypeSerializer<N> namespaceSerializer) throws StateMigrationException, IOException { Tuple2<ColumnFamilyHandle, RegisteredKeyedBackendStateMetaInfo<?, ?>> registeredInfo = this.kvStateInformation.get(stateDesc.getName()); if (registeredInfo != null) { @SuppressWarnings("unchecked") RegisteredKeyedBackendStateMetaInfo.Snapshot<?, ?> restoredMetaInfoSnapshot = restoredKvStateMetaInfos.get(stateDesc.getName()); Preconditions.checkState( restoredMetaInfoSnapshot != null, "Requested to check compatibility of a restored RegisteredKeyedBackendStateMetaInfo," + " but its corresponding restored snapshot cannot be found."); RegisteredKeyedBackendStateMetaInfo<N, S> resolveKvStateCompatibility = RegisteredKeyedBackendStateMetaInfo.resolveKvStateCompatibility( restoredMetaInfoSnapshot, namespaceSerializer, stateDesc); registeredInfo.f1 = resolveKvStateCompatibility; return Tuple2.of(registeredInfo.f0, resolveKvStateCompatibility); } else { String stateName = stateDesc.getName(); RegisteredKeyedBackendStateMetaInfo<N, S> newMetaInfo = new RegisteredKeyedBackendStateMetaInfo<>( stateDesc.getType(), stateName, namespaceSerializer, stateDesc.getSerializer()); ColumnFamilyHandle columnFamily = createColumnFamily(stateName); registeredInfo = Tuple2.of(columnFamily, newMetaInfo); this.kvStateInformation.put(stateDesc.getName(), registeredInfo); return Tuple2.of(columnFamily, newMetaInfo); } } ``` and get rid of all the individual casts. > RocksDB does not propagate reconfiguration of serializer to the states > ---------------------------------------------------------------------- > > Key: FLINK-8715 > URL: https://issues.apache.org/jira/browse/FLINK-8715 > Project: Flink > Issue Type: Bug > Components: State Backends, Checkpointing > Affects Versions: 1.3.2 > Reporter: Arvid Heise > Assignee: Tzu-Li (Gordon) Tai > Priority: Blocker > Fix For: 1.5.0 > > > Any changes to the serializer done in #ensureCompability are lost during the > state creation. > In particular, > [https://github.com/apache/flink/blob/master/flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBValueState.java#L68] > always uses a fresh copy of the StateDescriptor. > An easy fix is to pass the reconfigured serializer as an additional parameter > in > [https://github.com/apache/flink/blob/master/flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBKeyedStateBackend.java#L1681] > , which can be retrieved through the side-output of getColumnFamily > {code:java} > kvStateInformation.get(stateDesc.getName()).f1.getStateSerializer() > {code} > I encountered it in 1.3.2 but the code in the master seems unchanged (hence > the pointer into master). I encountered it in ValueState, but I suspect the > same issue can be observed for all kinds of RocksDB states. -- This message was sent by Atlassian JIRA (v7.6.3#76005)