KnightChess commented on code in PR #11578: URL: https://github.com/apache/hudi/pull/11578#discussion_r1668708594
########## hudi-common/src/main/java/org/apache/hudi/common/util/hash/BucketIndexUtil.java: ########## @@ -0,0 +1,45 @@ +/* + * 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.hudi.common.util.hash; + +import org.apache.hudi.common.util.Functions; + +/** + * Utility class for bucket index. + */ +public class BucketIndexUtil { + + /** + * This method is used to get the partition index calculation function of a bucket. + * "partition.hashCode() / (parallelism / bucketNum) * bucketNum" divides the parallelism into + * sub-intervals of length bucket_num, different partitions will be mapped to different sub-interval, + * ensure that the data across multiple partitions is evenly distributed. + * + * @param bucketNum Bucket number per partition + * @param parallelism Parallelism of the task + * @return The partition index of this bucket. + */ + public static Functions.Function2<String, Integer, Integer> getPartitionIndexFunc(int bucketNum, int parallelism) { + return (partition, curBucket) -> { + int partitionIndex = (partition.hashCode() & Integer.MAX_VALUE) % parallelism * bucketNum; + int globalIndex = partitionIndex + curBucket; Review Comment: @danny0405 what do you think about? -- 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: commits-unsubscr...@hudi.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
