8199712: Flight Recorder
Reviewed-by: coleenp, ihse, erikj, dsamersoff, mseledtsov, egahlin, mgronlun
Contributed-by: erik.gahlin@oracle.com, markus.gronlund@oracle.com
/*
* Copyright (c) 2018, Oracle 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package jdk.jfr.event.oldobject;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Callable;
import jdk.jfr.Recording;
import jdk.jfr.consumer.RecordedEvent;
import jdk.jfr.consumer.RecordedObject;
import jdk.jfr.internal.test.WhiteBox;
import jdk.test.lib.jfr.EventNames;
import jdk.test.lib.jfr.Events;
/*
* @test
* @key jfr
* @requires vm.gc == "null"
* @library /test/lib /test/jdk
* @modules jdk.jfr/jdk.jfr.internal.test
* @run main/othervm -XX:TLABSize=2k jdk.jfr.event.oldobject.TestObjectDescription
*/
public class TestObjectDescription {
private static final int OBJECT_DESCRIPTION_MAX_SIZE = 100;
private static final String CLASS_NAME = TestClassLoader.class.getName() + "$TestClass";
public static List<?> leaks;
public final static class MyThreadGroup extends ThreadGroup {
public final static String NAME = "My Thread Group";
public MyThreadGroup(String name) {
super(name);
}
// Allocate array to trigger sampling code path for interpreter / c1
byte[] bytes = new byte[10];
}
public final static class MyThread extends Thread {
public final static String NAME = "My Thread";
public MyThread() {
super(NAME);
}
// Allocate array to trigger sampling code path for interpreter / c1
byte[] bytes = new byte[10];
}
public static void main(String[] args) throws Exception {
WhiteBox.setWriteAllObjectSamples(true);
testThreadGroupName();
testThreadName();
testClassName();
testSize();
testEllipsis();
}
private static void testThreadName() throws Exception {
asseertObjectDescription(() -> {
List<MyThread> threads = new ArrayList<>(OldObjects.MIN_SIZE);
for (int i = 0; i < OldObjects.MIN_SIZE; i++) {
threads.add(new MyThread());
}
return threads;
}, "Thread Name: " + MyThread.NAME);
}
private static void testThreadGroupName() throws Exception {
asseertObjectDescription(() -> {
List<MyThreadGroup> groups = new ArrayList<>(OldObjects.MIN_SIZE);
for (int i = 0; i < OldObjects.MIN_SIZE; i++) {
groups.add(new MyThreadGroup("My Thread Group"));
}
return groups;
}, "Thread Group: " + "My Thread Group");
}
private static void testClassName() throws Exception {
asseertObjectDescription(() -> {
TestClassLoader testClassLoader = new TestClassLoader();
List<Object> classObjects = new ArrayList<>(OldObjects.MIN_SIZE);
for (Class<?> clazz : testClassLoader.loadClasses(OldObjects.MIN_SIZE / 20)) {
// Allocate array to trigger sampling code path for interpreter / c1
for (int i = 0; i < 20; i++) {
Object classArray = Array.newInstance(clazz, 20);
Array.set(classArray, i, clazz.newInstance());
classObjects.add(classArray);
}
}
return classObjects;
}, "Class Name: " + CLASS_NAME);
}
private static void testSize() throws Exception {
asseertObjectDescription(() -> {
List<Object> arrayLists = new ArrayList<>(OldObjects.MIN_SIZE);
for (int i = 0; i < OldObjects.MIN_SIZE; i++) {
List<Object> arrayList = new ArrayList<>();
arrayList.add(new Object());
arrayList.add(new Object());
arrayList.add(new Object());
arrayLists.add(arrayList);
}
return arrayLists;
}, "Size: 3");
}
private static void testEllipsis() throws Exception {
asseertObjectDescription(() -> {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < 2 * OBJECT_DESCRIPTION_MAX_SIZE; i++) {
sb.append("x");
}
String threadName = sb.toString();
List<Thread> threads = new ArrayList<>();
for (int i = 0; i < OldObjects.MIN_SIZE; i++) {
threads.add(new Thread(threadName));
}
return threads;
}, "xxx...");
}
private static void asseertObjectDescription(Callable<List<?>> callable, String text) throws Exception {
int iteration = 1;
while (true) {
try (Recording recording = new Recording()) {
System.out.println("Iteration: " + iteration);
recording.enable(EventNames.OldObjectSample).withoutStackTrace().with("cutoff", "infinity");
recording.start();
leaks = null;
System.gc();
leaks = callable.call();
recording.stop();
List<RecordedEvent> events = Events.fromRecording(recording);
Set<String> objectDescriptions = extractObjectDecriptions(events);
for (String s : objectDescriptions) {
if (s.contains(text)) {
printDescriptions(objectDescriptions);
return;
}
}
System.out.println("Could not find object description containing text \"" + text + "\"");
printDescriptions(objectDescriptions);
System.out.println();
iteration++;
}
}
}
private static void printDescriptions(Set<String> objectDescriptions) {
System.out.println("Found descriptions:");
for (String t : objectDescriptions) {
System.out.println(t);
}
}
private static Set<String> extractObjectDecriptions(List<RecordedEvent> events) {
Set<String> objectDescriptions = new HashSet<>();
for (RecordedEvent e : events) {
objectDescriptions.addAll(extractObjectDescriptions(e.getValue("object")));
}
return objectDescriptions;
}
private static Set<String> extractObjectDescriptions(RecordedObject o) {
Set<Long> visited = new HashSet<>();
Set<String> descriptions = new HashSet<>();
while (o != null) {
Long memoryAddress = o.getValue("address");
if (visited.contains(memoryAddress)) {
return descriptions;
}
visited.add(memoryAddress);
String od = o.getValue("description");
if (od != null) {
descriptions.add(od);
}
RecordedObject referrer = o.getValue("referrer");
o = referrer != null ? referrer.getValue("object") : null;
}
return descriptions;
}
}