yashmayya commented on code in PR #15990: URL: https://github.com/apache/pinot/pull/15990#discussion_r2136889039
########## pinot-controller/src/main/java/org/apache/pinot/controller/helix/core/rebalance/TableRebalanceManager.java: ########## @@ -0,0 +1,235 @@ +/** + * 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.pinot.controller.helix.core.rebalance; + +import com.google.common.annotations.VisibleForTesting; +import com.google.common.base.Preconditions; +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.CompletableFuture; +import java.util.concurrent.ExecutorService; +import javax.annotation.Nullable; +import org.apache.pinot.common.exception.TableNotFoundException; +import org.apache.pinot.common.metadata.controllerjob.ControllerJobType; +import org.apache.pinot.common.metrics.ControllerMetrics; +import org.apache.pinot.controller.helix.core.PinotHelixResourceManager; +import org.apache.pinot.controller.util.TableSizeReader; +import org.apache.pinot.spi.config.table.TableConfig; +import org.apache.pinot.spi.utils.CommonConstants; +import org.apache.pinot.spi.utils.JsonUtils; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +/** + * Single entry point for all table rebalance related operations. This class should be used to initiate table rebalance + * operations, rather than directly instantiating objects of {@link TableRebalancer}. + */ +public class TableRebalanceManager { + private static final Logger LOGGER = LoggerFactory.getLogger(TableRebalanceManager.class); + + private final PinotHelixResourceManager _resourceManager; + private final ControllerMetrics _controllerMetrics; + private final RebalancePreChecker _rebalancePreChecker; + private final TableSizeReader _tableSizeReader; + private final ExecutorService _executorService; + + public TableRebalanceManager(PinotHelixResourceManager resourceManager, ControllerMetrics controllerMetrics, + RebalancePreChecker rebalancePreChecker, TableSizeReader tableSizeReader, ExecutorService executorService) { + _resourceManager = resourceManager; + _controllerMetrics = controllerMetrics; + _rebalancePreChecker = rebalancePreChecker; + _tableSizeReader = tableSizeReader; + _executorService = executorService; + } + + /** + * Rebalance the table with the given name and type synchronously. It's the responsibility of the caller to ensure Review Comment: This is the synchronous table rebalance API which performs rebalances on the caller's thread. The async APIs will perform the rebalance on the rebalance executor thread pool which is configured based on the controller config. These sync APIs are present for use cases like dry run rebalance requests, segment relocator initiated rebalances (done on the separate controller thread pool like you pointed out in another comment), and tenant rebalances (which use the same rebalance thread pool internally, and this API allows for more flexible coupling). I think it's important to call out this caveat in the method's Javadoc so that new usages are thought through carefully. -- 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...@pinot.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
