pvary commented on code in PR #10308: URL: https://github.com/apache/iceberg/pull/10308#discussion_r1608725056
########## flink/v1.19/flink/src/main/java/org/apache/iceberg/flink/maintenance/operator/SingleThreadedIteratorSource.java: ########## @@ -0,0 +1,196 @@ +/* + * 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.iceberg.flink.maintenance.operator; + +import java.io.IOException; +import java.io.Serializable; +import java.util.Collection; +import java.util.Iterator; +import org.apache.flink.api.connector.source.Source; +import org.apache.flink.api.connector.source.SourceReader; +import org.apache.flink.api.connector.source.SourceReaderContext; +import org.apache.flink.api.connector.source.SplitEnumerator; +import org.apache.flink.api.connector.source.SplitEnumeratorContext; +import org.apache.flink.api.connector.source.lib.util.IteratorSourceEnumerator; +import org.apache.flink.api.connector.source.lib.util.IteratorSourceReader; +import org.apache.flink.api.connector.source.lib.util.IteratorSourceSplit; +import org.apache.flink.api.java.typeutils.ResultTypeQueryable; +import org.apache.flink.core.io.SimpleVersionedSerializer; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.relocated.com.google.common.collect.ImmutableList; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; + +/** + * Implementation of the Source V2 API which uses an iterator to read the elements, and uses a + * single thread to do so. + * + * @param <T> The return type of the source + */ +public abstract class SingleThreadedIteratorSource<T> Review Comment: I think it is for the best if we preaggregate as many of the TableChanges as possible. Otherwise we might end up triggering unnecessary rewrites. Let's say, we have S1 (2 new files), S2 (3 new files), S3 (2 new files), S4 (3 new files), and we have set that we need manifest file compaction after 2 commits. If we end up reading the snapshots parallel, then we might end up running the manifest rewrite task 4 times. The good solution would be to run it a single time. I do not expect that the `MonitorSource` will need the parallelisation anyways. It would add complexity, and extra resource usage with no benefits. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
