rpuch commented on code in PR #6370: URL: https://github.com/apache/ignite-3/pull/6370#discussion_r2262106540
########## modules/network/src/main/java/org/apache/ignite/internal/network/handshake/HandshakeEventLoopSwitcher.java: ########## @@ -0,0 +1,155 @@ +/* + * 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.ignite.internal.network.handshake; + +import static org.apache.ignite.internal.util.CompletableFutures.nullCompletedFuture; + +import io.netty.channel.Channel; +import io.netty.channel.ChannelId; +import io.netty.channel.EventLoop; +import java.util.HashMap; +import java.util.HashSet; +import java.util.List; +import java.util.Set; +import java.util.concurrent.CompletableFuture; +import org.apache.ignite.internal.logger.IgniteLogger; +import org.apache.ignite.internal.logger.Loggers; + +/** + * A class responsible for managing the assignment of Netty channels to event loops + * and switching channels between event loops when necessary. + */ +public class HandshakeEventLoopSwitcher { + private static final IgniteLogger LOG = Loggers.forClass(HandshakeEventLoopSwitcher.class); + + /** List of available event loops. */ + private final List<EventLoop> executors; + /** Map to track the number of channels assigned to each event loop. */ + private final HashMap<Integer, Set<ChannelId>> channelCountMap; + + /** + * Constructs a new instance of HandshakeEventLoopSwitcher. + * + * @param eventLoops The list of event loops to manage. + */ + public HandshakeEventLoopSwitcher(List<EventLoop> eventLoops) { + this.executors = eventLoops; + this.channelCountMap = new HashMap<>(eventLoops.size()); + } + + /** + * Switches the event loop of a given channel if needed. + * + * @param channel The channel to potentially switch to a different event loop. + * @param afterSwitching A callback to execute after the switching operation. + * @return A CompletableFuture that completes when the event loop is switched. + */ + public CompletableFuture<Void> switchEventLoopIfNeeded(Channel channel, Runnable afterSwitching) { + EventLoop targetEventLoop = eventLoopForKey(channel.id()); + + if (targetEventLoop != channel.eventLoop()) { + CompletableFuture<Void> fut = new CompletableFuture<>(); + + channel.deregister().addListener(deregistrationFuture -> { + if (!deregistrationFuture.isSuccess()) { + LOG.error("Cannot deregister a channel from an event loop", deregistrationFuture.cause()); + + fut.completeExceptionally(deregistrationFuture.cause()); + + channel.close(); + + return; + } + + targetEventLoop.register(channel).addListener(registrationFuture -> { + if (!registrationFuture.isSuccess()) { + LOG.error("Cannot register a channel with an event loop", registrationFuture.cause()); + + fut.completeExceptionally(deregistrationFuture.cause()); + + channel.close(); + + return; + } + + channel.closeFuture().addListener(future -> { + channelUnregistered(channel); + }); + + fut.complete(null); + + afterSwitching.run(); + }); + }); + + return fut; + } + + afterSwitching.run(); + + return nullCompletedFuture(); + } + + /** + * Determines the appropriate event loop for a given channel ID. + * + * @param channelId The ID of the channel. + * @return The selected event loop for the channel. + */ + private synchronized EventLoop eventLoopForKey(ChannelId channelId) { + int minCnt = channelCountMap.getOrDefault(0, Set.of()).size(); + int index = 0; + + for (int i = 1; i < executors.size(); i++) { + Set<ChannelId> channelIds = channelCountMap.getOrDefault(i, Set.of()); + + if (channelIds.contains(channelId)) { + return executors.get(index); + } + + int cnt = channelIds.size(); + + if (cnt < minCnt) { + minCnt = cnt; + index = i; + } + } + Review Comment: I mean, there are two blank lines in a row; it's not about the trailing line break -- 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: notifications-unsubscr...@ignite.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
