| /** |
| * 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.bookkeeper.util; |
| |
| import io.netty.channel.EventLoopGroup; |
| import io.netty.channel.SelectStrategy; |
| import io.netty.channel.epoll.EpollEventLoopGroup; |
| import io.netty.channel.nio.NioEventLoopGroup; |
| |
| import java.util.concurrent.ThreadFactory; |
| |
| import lombok.experimental.UtilityClass; |
| import lombok.extern.slf4j.Slf4j; |
| |
| import org.apache.bookkeeper.common.util.affinity.CpuAffinity; |
| import org.apache.bookkeeper.conf.ClientConfiguration; |
| import org.apache.bookkeeper.conf.ServerConfiguration; |
| import org.apache.commons.lang.SystemUtils; |
| |
| |
| /** |
| * Utility class to initialize Netty event loops. |
| */ |
| @Slf4j |
| @UtilityClass |
| public class EventLoopUtil { |
| public static EventLoopGroup getClientEventLoopGroup(ClientConfiguration conf, ThreadFactory threadFactory) { |
| return getEventLoopGroup(threadFactory, conf.getNumIOThreads(), conf.isBusyWaitEnabled()); |
| } |
| |
| public static EventLoopGroup getServerEventLoopGroup(ServerConfiguration conf, ThreadFactory threadFactory) { |
| return getEventLoopGroup(threadFactory, conf.getServerNumIOThreads(), conf.isBusyWaitEnabled()); |
| } |
| |
| private static EventLoopGroup getEventLoopGroup(ThreadFactory threadFactory, |
| int numThreads, boolean enableBusyWait) { |
| if (!SystemUtils.IS_OS_LINUX) { |
| return new NioEventLoopGroup(numThreads, threadFactory); |
| } |
| |
| try { |
| if (!enableBusyWait) { |
| // Regular Epoll based event loop |
| return new EpollEventLoopGroup(numThreads, threadFactory); |
| } |
| |
| // With low latency setting, put the Netty event loop on busy-wait loop to reduce cost of |
| // context switches |
| EpollEventLoopGroup eventLoopGroup = new EpollEventLoopGroup(numThreads, threadFactory, |
| () -> (selectSupplier, hasTasks) -> SelectStrategy.BUSY_WAIT); |
| |
| // Enable CPU affinity on IO threads |
| for (int i = 0; i < numThreads; i++) { |
| eventLoopGroup.next().submit(() -> { |
| try { |
| CpuAffinity.acquireCore(); |
| } catch (Throwable t) { |
| log.warn("Failed to acquire CPU core for thread {}", Thread.currentThread().getName(), |
| t.getMessage(), t); |
| } |
| }); |
| } |
| |
| return eventLoopGroup; |
| } catch (ExceptionInInitializerError | NoClassDefFoundError | UnsatisfiedLinkError e) { |
| log.warn("Could not use Netty Epoll event loop: {}", e.getMessage()); |
| return new NioEventLoopGroup(numThreads, threadFactory); |
| } |
| } |
| } |