1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package com.github.dexecutor.executor.support; 19 20 /** 21 * 22 * @author Nadeem Mohammad 23 * 24 */ 25 public final class ThreadPoolUtil { 26 27 private ThreadPoolUtil() { 28 29 } 30 /** 31 * Each tasks blocks 90% of the time, and works only 10% of its 32 * lifetime. That is, I/O intensive pool 33 * @return io intesive Thread pool size 34 */ 35 public static int ioIntesivePoolSize() { 36 37 double blockingCoefficient = 0.9; 38 return poolSize(blockingCoefficient); 39 } 40 41 /** 42 * 43 * Number of threads = Number of Available Cores / (1 - Blocking 44 * Coefficient) where the blocking coefficient is between 0 and 1. 45 * 46 * A computation-intensive task has a blocking coefficient of 0, whereas an 47 * IO-intensive task has a value close to 1, 48 * so we don't have to worry about the value reaching 1. 49 * @param blockingCoefficient 50 * @return Thread pool size 51 */ 52 public static int poolSize(double blockingCoefficient) { 53 int numberOfCores = Runtime.getRuntime().availableProcessors(); 54 int poolSize = (int) (numberOfCores / (1 - blockingCoefficient)); 55 return poolSize; 56 } 57 }