1 /* 2 * Copyright (c) 2017, Google 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 */ 23 24 package MyPackage; 25 26 /** 27 * @test 28 * @summary Checks the frequent garbage storage system. 29 * @build Frame 30 * @compile HeapMonitorFrequentTest.java 31 * @run main/othervm/native -agentlib:HeapMonitor MyPackage.HeapMonitorFrequentTest 32 */ 33 34 public class HeapMonitorFrequentTest { 35 36 static { 37 try { 38 System.loadLibrary("HeapMonitor"); 39 } catch (UnsatisfiedLinkError ule) { 40 System.err.println("Could not load HeapMonitor library"); 41 System.err.println("java.library.path: " 42 + System.getProperty("java.library.path")); 43 throw ule; 44 } 45 } 46 47 private native static int checkFrequentFrames(Frame[] frames); 48 private native static int enableSampling(); 49 50 private static int g_tmp[]; 51 52 private static int helper() { 53 int sum = 0; 54 // Let us assume that the array is 24 bytes of memory. 55 for (int i = 0; i < 127000 / 6; i++) { 56 int tmp[] = new int[1]; 57 // Force it to be kept. 58 g_tmp = tmp; 59 sum += g_tmp[0]; 60 } 61 return sum; 62 } 63 64 private static void runner(int max) { 65 int sum = 0; 66 for (int j = 0; j < max; j++) { 67 sum += helper(); 68 } 69 System.out.println(sum); 70 } 71 72 public static void main(String[] args) { 73 Frame[] frames = new Frame[3]; 74 frames[0] = new Frame("helper", "()I", "HeapMonitorRecentTest.java", 60); 75 frames[1] = new Frame("runner", "(I)V", "HeapMonitorRecentTest.java", 71); 76 frames[2] = new Frame("main", "([Ljava/lang/String;)V", "HeapMonitorRecentTest.java", 85); 77 78 enableSampling(); 79 // We are testing for the recent garbage sampler: 80 // First run for 10000 iterations to fill up the garbage sampler. 81 runner(10000); 82 83 // Now because we are in a different stack frame line here, we can just re-use the same runner. 84 // Run for 3, we really should not see that many of these and most should be the first type. 85 runner(5000); 86 87 // Both types should exist in frequent since it was frequent enough. 88 int status = checkFrequentFrames(frames); 89 if (status == 0) { 90 throw new RuntimeException("Old frames no longer exist"); 91 } 92 93 // Change the last frame only since the rest is identical. 94 frames[2].lineNumber = 89; 95 96 status = checkFrequentFrames(frames); 97 if (status == 0) { 98 throw new RuntimeException("New frames not in the frequent sampling list"); 99 } 100 } 101 }