satishd commented on a change in pull request #10579: URL: https://github.com/apache/kafka/pull/10579#discussion_r663821465
########## File path: storage/src/main/java/org/apache/kafka/server/log/remote/metadata/storage/TopicBasedRemoteLogMetadataManager.java ########## @@ -0,0 +1,360 @@ +/* + * 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.kafka.server.log.remote.metadata.storage; + +import org.apache.kafka.clients.producer.RecordMetadata; +import org.apache.kafka.common.KafkaException; +import org.apache.kafka.common.TopicIdPartition; +import org.apache.kafka.common.errors.RetriableException; +import org.apache.kafka.common.utils.KafkaThread; +import org.apache.kafka.common.utils.Time; +import org.apache.kafka.common.utils.Utils; +import org.apache.kafka.server.log.remote.storage.RemoteLogMetadata; +import org.apache.kafka.server.log.remote.storage.RemoteLogMetadataManager; +import org.apache.kafka.server.log.remote.storage.RemoteLogSegmentMetadata; +import org.apache.kafka.server.log.remote.storage.RemoteLogSegmentMetadataUpdate; +import org.apache.kafka.server.log.remote.storage.RemoteLogSegmentState; +import org.apache.kafka.server.log.remote.storage.RemotePartitionDeleteMetadata; +import org.apache.kafka.server.log.remote.storage.RemoteStorageException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.io.IOException; +import java.util.HashSet; +import java.util.Iterator; +import java.util.Map; +import java.util.Objects; +import java.util.Optional; +import java.util.Set; +import java.util.concurrent.atomic.AtomicBoolean; +import java.util.concurrent.locks.ReentrantReadWriteLock; + +/** + * This is the {@link RemoteLogMetadataManager} implementation with storage as an internal topic with name {@link TopicBasedRemoteLogMetadataManagerConfig#REMOTE_LOG_METADATA_TOPIC_NAME}. + * This is used to publish and fetch {@link RemoteLogMetadata} for the registered user topic partitions with + * {@link #onPartitionLeadershipChanges(Set, Set)}. Each broker will have an instance of this class and it subscribes + * to metadata updates for the registered user topic partitions. + */ +public class TopicBasedRemoteLogMetadataManager implements RemoteLogMetadataManager { + private static final Logger log = LoggerFactory.getLogger(TopicBasedRemoteLogMetadataManager.class); + + private volatile boolean configured = false; + + // It indicates whether the close process of this instance is started or not via #close() method. + // Using AtomicBoolean instead of volatile as it may encounter http://findbugs.sourceforge.net/bugDescriptions.html#SP_SPIN_ON_FIELD + // if the field is read but not updated in a spin loop like in #initializeResources() method. + private final AtomicBoolean closing = new AtomicBoolean(false); Review comment: `closing` is accessed in `initializeResources` and we do not need to take a lock there. I would like to keep this as `AtomicBoolean` which addresses that and it is easy to understand the semantics. -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
