/*
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* 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
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*/
/*
* @test
* @bug 4530538
* @summary Basic unit test of memory management testing:
* 1) setUsageThreshold() and getUsageThreshold()
* 2) test low memory detection on the old generation.
* @author Mandy Chung
*
* @requires vm.gc == "null"
* @requires vm.opt.ExplicitGCInvokesConcurrent != "true"
* @requires vm.opt.DisableExplicitGC != "true"
* @library /test/lib
*
* @build LowMemoryTest MemoryUtil RunUtil
* @build sun.hotspot.WhiteBox
* @run driver ClassFileInstaller sun.hotspot.WhiteBox sun.hotspot.WhiteBox$WhiteBoxPermission
* @run main/othervm/timeout=600 -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. LowMemoryTest
*/
import java.lang.management.*;
import java.util.*;
import java.util.concurrent.Phaser;
import javax.management.*;
import javax.management.openmbean.CompositeData;
import jdk.test.lib.JDKToolFinder;
import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.Utils;
import sun.hotspot.code.Compiler;
public class LowMemoryTest {
private static final MemoryMXBean mm = ManagementFactory.getMemoryMXBean();
private static final List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
private static final Phaser phaser = new Phaser(2);
private static MemoryPoolMXBean mpool = null;
private static boolean trace = false;
private static boolean testFailed = false;
private static final int NUM_TRIGGERS = 5;
private static final int NUM_CHUNKS = 2;
private static final int YOUNG_GEN_SIZE = 8 * 1024 * 1024;
private static long chunkSize;
private static final String classMain = "LowMemoryTest$TestMain";
/**
* Run the test multiple times with different GC versions.
* First with default command line specified by the framework.
* Then with GC versions specified by the test.
*/
public static void main(String a[]) throws Throwable {
// Use a low young gen size to ensure that the
// allocated objects are put in the old gen.
final String nmFlag = "-Xmn" + YOUNG_GEN_SIZE;
// Using large pages will change the young gen size,
// make sure we don't use them for this test.
final String lpFlag = "-XX:-UseLargePages";
// Prevent G1 from selecting a large heap region size,
// since that would change the young gen size.
final String g1Flag = "-XX:G1HeapRegionSize=1m";
// Runs the test collecting subprocess I/O while it's running.
traceTest(classMain + ", -XX:+UseSerialGC", nmFlag, lpFlag, "-XX:+UseSerialGC");
traceTest(classMain + ", -XX:+UseParallelGC", nmFlag, lpFlag, "-XX:+UseParallelGC");
traceTest(classMain + ", -XX:+UseG1GC", nmFlag, lpFlag, "-XX:+UseG1GC", g1Flag);
if (!Compiler.isGraalEnabled()) { // Graal does not support CMS
traceTest(classMain + ", -XX:+UseConcMarkSweepGC", nmFlag, lpFlag, "-XX:+UseConcMarkSweepGC");
}
}
/*
* Creating command-line for running subprocess JVM:
*
* JVM command line is like:
* {test_jdk}/bin/java {defaultopts} -cp {test.class.path} {testopts} main
*
* {defaultopts} are the default java options set by the framework.
*
* @param testOpts java options specified by the test.
*/
private static List<String> buildCommandLine(String... testOpts) {
List<String> opts = new ArrayList<>();
opts.add(JDKToolFinder.getJDKTool("java"));
opts.addAll(Arrays.asList(Utils.getTestJavaOpts()));
opts.add("-cp");
opts.add(System.getProperty("test.class.path", "test.class.path"));
opts.add("-Xlog:gc*=debug");
opts.addAll(Arrays.asList(testOpts));
opts.add(classMain);
return opts;
}
/**
* Runs LowMemoryTest$TestMain with the passed options and redirects subprocess
* standard I/O to the current (parent) process. This provides a trace of what
* happens in the subprocess while it is runnning (and before it terminates).
*
* @param prefixName the prefix string for redirected outputs
* @param testOpts java options specified by the test.
*/
private static void traceTest(String prefixName,
String... testOpts)
throws Throwable {
// Building command-line
List<String> opts = buildCommandLine(testOpts);
// We activate all tracing in subprocess
opts.add("trace");
// Launch separate JVM subprocess
String[] optsArray = opts.toArray(new String[0]);
ProcessBuilder pb = new ProcessBuilder(optsArray);
System.out.println("\n========= Tracing of subprocess " + prefixName + " =========");
Process p = ProcessTools.startProcess(prefixName, pb);
// Handling end of subprocess
try {
int exitCode = p.waitFor();
if (exitCode != 0) {
throw new RuntimeException(
"Subprocess unexpected exit value of [" + exitCode + "]. Expected 0.\n");
}
} catch (InterruptedException e) {
throw new RuntimeException("Parent process interrupted with exception : \n " + e + " :" );
}
}
private static volatile boolean listenerInvoked = false;
static class SensorListener implements NotificationListener {
@Override
public void handleNotification(Notification notif, Object handback) {
String type = notif.getType();
if (type.equals(MemoryNotificationInfo.MEMORY_THRESHOLD_EXCEEDED) ||
type.equals(MemoryNotificationInfo.
MEMORY_COLLECTION_THRESHOLD_EXCEEDED)) {
MemoryNotificationInfo minfo = MemoryNotificationInfo.
from((CompositeData) notif.getUserData());
MemoryUtil.printMemoryNotificationInfo(minfo, type);
listenerInvoked = true;
}
}
}
static class TestListener implements NotificationListener {
private boolean isRelaxed = false;
private int triggers = 0;
private final long[] count = new long[NUM_TRIGGERS * 2];
private final long[] usedMemory = new long[NUM_TRIGGERS * 2];
public TestListener() {
isRelaxed = ManagementFactory.getRuntimeMXBean().getInputArguments().contains("-XX:+UseConcMarkSweepGC");
}
@Override
public void handleNotification(Notification notif, Object handback) {
MemoryNotificationInfo minfo = MemoryNotificationInfo.
from((CompositeData) notif.getUserData());
count[triggers] = minfo.getCount();
usedMemory[triggers] = minfo.getUsage().getUsed();
triggers++;
}
public void checkResult() throws Exception {
if (!checkValue(triggers, NUM_TRIGGERS)) {
throw new RuntimeException("Unexpected number of triggers = " +
triggers + " but expected to be " + NUM_TRIGGERS);
}
for (int i = 0; i < triggers; i++) {
if (!checkValue(count[i], i + 1)) {
throw new RuntimeException("Unexpected count of" +
" notification #" + i +
" count = " + count[i] +
" but expected to be " + (i+1));
}
if (usedMemory[i] < newThreshold) {
throw new RuntimeException("Used memory = " +
usedMemory[i] + " is less than the threshold = " +
newThreshold);
}
}
}
private boolean checkValue(int value, int target) {
return checkValue((long)value, target);
}
private boolean checkValue(long value, int target) {
if (!isRelaxed) {
return value == target;
} else {
return value >= target;
}
}
}
private static long newThreshold;
private static class TestMain {
public static void main(String args[]) throws Exception {
if (args.length > 0 && args[0].equals("trace")) {
trace = true;
}
// Find the Old generation which supports low memory detection
ListIterator iter = pools.listIterator();
while (iter.hasNext()) {
MemoryPoolMXBean p = (MemoryPoolMXBean) iter.next();
if (p.getType() == MemoryType.HEAP &&
p.isUsageThresholdSupported()) {
mpool = p;
if (trace) {
System.out.println("Selected memory pool for low memory " +
"detection.");
MemoryUtil.printMemoryPool(mpool);
}
break;
}
}
TestListener listener = new TestListener();
SensorListener l2 = new SensorListener();
NotificationEmitter emitter = (NotificationEmitter) mm;
emitter.addNotificationListener(listener, null, null);
emitter.addNotificationListener(l2, null, null);
Thread allocator = new AllocatorThread();
Thread sweeper = new SweeperThread();
// The chunk size needs to be larger than YOUNG_GEN_SIZE,
// otherwise we will get intermittent failures when objects
// end up in the young gen instead of the old gen.
final long epsilon = 1024;
chunkSize = YOUNG_GEN_SIZE + epsilon;
MemoryUsage mu = mpool.getUsage();
newThreshold = mu.getUsed() + (chunkSize * NUM_CHUNKS);
// Sanity check. Make sure the new threshold isn't too large.
// Tweak the test if this fails.
final long headRoom = chunkSize * 2;
final long max = mu.getMax();
if (max != -1 && newThreshold > max - headRoom) {
throw new RuntimeException("TEST FAILED: newThreshold: " + newThreshold +
" is too near the maximum old gen size: " + max +
" used: " + mu.getUsed() + " headRoom: " + headRoom);
}
System.out.println("Setting threshold for " + mpool.getName() +
" from " + mpool.getUsageThreshold() + " to " + newThreshold +
". Current used = " + mu.getUsed());
mpool.setUsageThreshold(newThreshold);
if (mpool.getUsageThreshold() != newThreshold) {
throw new RuntimeException("TEST FAILED: " +
"Threshold for Memory pool " + mpool.getName() +
"is " + mpool.getUsageThreshold() + " but expected to be" +
newThreshold);
}
allocator.start();
// Force Allocator start first
phaser.arriveAndAwaitAdvance();
sweeper.start();
try {
allocator.join();
// Wait until AllocatorThread's done
phaser.arriveAndAwaitAdvance();
sweeper.join();
} catch (InterruptedException e) {
System.out.println("Unexpected exception:" + e);
testFailed = true;
}
listener.checkResult();
if (testFailed)
throw new RuntimeException("TEST FAILED.");
System.out.println(RunUtil.successMessage);
}
}
private static void goSleep(long ms) {
try {
Thread.sleep(ms);
} catch (InterruptedException e) {
System.out.println("Unexpected exception:" + e);
testFailed = true;
}
}
private static final List<Object> objectPool = new ArrayList<>();
static class AllocatorThread extends Thread {
public void doTask() {
int iterations = 0;
int numElements = (int) (chunkSize / 4); // minimal object size
while (!listenerInvoked || mpool.getUsage().getUsed() < mpool.getUsageThreshold()) {
iterations++;
if (trace) {
System.out.println(" Iteration " + iterations +
": before allocation " +
mpool.getUsage().getUsed());
}
Object[] o = new Object[numElements];
if (iterations <= NUM_CHUNKS) {
// only hold a reference to the first NUM_CHUNKS
// allocated objects
objectPool.add(o);
}
if (trace) {
System.out.println(" " +
" after allocation " +
mpool.getUsage().getUsed());
}
goSleep(100);
}
}
@Override
public void run() {
for (int i = 1; i <= NUM_TRIGGERS; i++) {
// Sync with SweeperThread's second phase.
phaser.arriveAndAwaitAdvance();
System.out.println("AllocatorThread is doing task " + i +
" phase " + phaser.getPhase());
doTask();
// Sync with SweeperThread's first phase.
phaser.arriveAndAwaitAdvance();
System.out.println("AllocatorThread done task " + i +
" phase " + phaser.getPhase());
if (testFailed) {
return;
}
}
}
}
static class SweeperThread extends Thread {
private void doTask() {
int iterations = 0;
if (trace) {
System.out.println("SweeperThread clearing allocated objects.");
}
for (; mpool.getUsage().getUsed() >=
mpool.getUsageThreshold();) {
// clear all allocated objects and invoke GC
objectPool.clear();
mm.gc();
if (trace) {
iterations++;
System.out.println("SweeperThread called " + iterations +
" time(s) MemoryMXBean.gc().");
}
goSleep(100);
}
}
@Override
public void run() {
for (int i = 1; i <= NUM_TRIGGERS; i++) {
// Sync with AllocatorThread's first phase.
phaser.arriveAndAwaitAdvance();
System.out.println("SweeperThread is doing task " + i +
" phase " + phaser.getPhase());
doTask();
listenerInvoked = false;
// Sync with AllocatorThread's second phase.
phaser.arriveAndAwaitAdvance();
System.out.println("SweeperThread done task " + i +
" phase " + phaser.getPhase());
if (testFailed) return;
}
}
}
}