| /* |
| * Copyright (c) 2018, Google and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package MyPackage; |
| |
| /** |
| * @test |
| * @summary Verifies the JVMTI Heap Monitor sampling interval average. |
| * @build Frame HeapMonitor |
| * @compile HeapMonitorStatIntervalTest.java |
| * @requires vm.compMode != "Xcomp" |
| * @run main/othervm/native -agentlib:HeapMonitorTest MyPackage.HeapMonitorStatIntervalTest |
| */ |
| |
| public class HeapMonitorStatIntervalTest { |
| private static boolean testIntervalOnce(int interval, boolean throwIfFailure) { |
| HeapMonitor.resetEventStorage(); |
| HeapMonitor.setSamplingInterval(interval); |
| |
| HeapMonitor.enableSamplingEvents(); |
| |
| int allocationTotal = 10 * 1024 * 1024; |
| int allocationIterations = 10; |
| |
| double actualCount = 0; |
| for (int i = 0; i < allocationIterations; i++) { |
| HeapMonitor.resetEventStorage(); |
| HeapMonitor.allocateSize(allocationTotal); |
| actualCount += HeapMonitor.getEventStorageElementCount(); |
| } |
| |
| HeapMonitor.disableSamplingEvents(); |
| |
| double expectedCount = allocationTotal * allocationIterations / interval; |
| |
| double error = Math.abs(actualCount - expectedCount); |
| double errorPercentage = error / expectedCount * 100; |
| |
| boolean success = (errorPercentage < 10.0); |
| |
| if (!success && throwIfFailure) { |
| throw new RuntimeException("Interval average over 10% for interval " + interval + " -> " |
| + actualCount + ", " + expectedCount); |
| } |
| |
| return success; |
| } |
| |
| |
| private static void testInterval(int interval) { |
| // Test the interval twice, it can happen that the test is "unlucky" and the interval just goes above |
| // the 10% mark. So try again to squash flakiness. |
| // Flakiness is due to the fact that this test is dependent on the sampling interval, which is a |
| // statistical geometric variable around the sampling interval. This means that the test could be |
| // unlucky and not achieve the mean average fast enough for the test case. |
| if (!testIntervalOnce(interval, false)) { |
| testIntervalOnce(interval, true); |
| } |
| } |
| |
| public static void main(String[] args) { |
| int[] tab = {1024, 8192}; |
| |
| HeapMonitor.calculateAverageOneElementSize(); |
| |
| for (int intervalIdx = 0; intervalIdx < tab.length; intervalIdx++) { |
| testInterval(tab[intervalIdx]); |
| } |
| } |
| } |