1/* 2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23package utils; 24 25import java.lang.management.ManagementFactory; 26import java.lang.management.MemoryPoolMXBean; 27 28/** 29 * Utility to obtain memory pools statistics 30 * 31 */ 32public class Pools { 33 34 private static final String EDEN_SPACE_POOL = "Eden Space"; 35 private static final String OLD_GEN_POOL = "Old Gen"; 36 private static final String METASPACE_POOL = "Metaspace"; 37 private static final String SURVIVOR_SPACE = "Survivor Space"; 38 39 public static long getNGMaxSize() { 40 // NewGen is consists of Eden and two Survivor spaces 41 return getPoolMaxSize(EDEN_SPACE_POOL) + 2 * getPoolMaxSize(SURVIVOR_SPACE); 42 } 43 44 public static long getHeapCommittedSize() { 45 return ManagementFactory.getMemoryMXBean().getHeapMemoryUsage().getCommitted() / 1024; 46 } 47 48 public static long getEdenCommittedSize() { 49 return getPoolCommittedSize(EDEN_SPACE_POOL); 50 } 51 52 public static long getOldGenCommittedSize() { 53 return getPoolCommittedSize(OLD_GEN_POOL); 54 } 55 56 public static long getMetaspaceCommittedSize() { 57 return getPoolCommittedSize(METASPACE_POOL); 58 } 59 60 private static long getPoolMaxSize(String poolName) { 61 long result; 62 MemoryPoolMXBean pool = findPool(poolName); 63 if (pool != null) { 64 if (pool.getUsage().getMax() == -1) { 65 result = -1; 66 } else { 67 result = pool.getUsage().getCommitted() / 1024; 68 } 69 } else { 70 throw new RuntimeException("Pool '" + poolName + "' wasn't found"); 71 } 72 log("Max size of the pool '" + poolName + "' is " + result); 73 return result; 74 } 75 76 private static long getPoolCommittedSize(String poolName) { 77 long result; 78 MemoryPoolMXBean pool = findPool(poolName); 79 if (pool != null) { 80 if (pool.getUsage().getCommitted() == -1) { 81 result = -1; 82 } else { 83 result = pool.getUsage().getCommitted() / 1024; 84 } 85 } else { 86 throw new RuntimeException("Pool '" + poolName + "' wasn't found"); 87 } 88 log("Committed size of the pool '" + poolName + "' is " + result); 89 return result; 90 } 91 92 private static MemoryPoolMXBean findPool(String poolName) { 93 for (MemoryPoolMXBean pool : ManagementFactory.getMemoryPoolMXBeans()) { 94 if (pool.getName().contains(poolName)) { 95 return pool; 96 } 97 } 98 return null; 99 } 100 101 private static void log(String s) { 102 System.out.println(s); 103 } 104 105} 106