| /* |
| * Copyright (c) 2016, 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. |
| * |
| * 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. |
| */ |
| |
| import java.io.PrintStream; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Random; |
| import sun.hotspot.WhiteBox; |
| |
| /* |
| * @test TestMultiThreadStressRSet.java |
| * @key stress |
| * @requires vm.gc=="G1" | vm.gc=="null" |
| * @requires os.maxMemory > 2G |
| * |
| * @summary Stress G1 Remembered Set using multiple threads |
| * @library /test/lib /testlibrary |
| * @build sun.hotspot.WhiteBox |
| * @run main ClassFileInstaller sun.hotspot.WhiteBox |
| * sun.hotspot.WhiteBox$WhiteBoxPermission |
| * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI |
| * -XX:+UseG1GC -XX:G1SummarizeRSetStatsPeriod=1 -Xlog:gc |
| * -Xmx500m -XX:G1HeapRegionSize=1m -XX:MaxGCPauseMillis=1000 TestMultiThreadStressRSet 10 4 |
| * |
| * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI |
| * -XX:+UseG1GC -XX:G1SummarizeRSetStatsPeriod=100 -Xlog:gc |
| * -Xmx1G -XX:G1HeapRegionSize=8m -XX:MaxGCPauseMillis=1000 TestMultiThreadStressRSet 60 16 |
| * |
| * @run main/othervm/timeout=700 -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI |
| * -XX:+UseG1GC -XX:G1SummarizeRSetStatsPeriod=100 -Xlog:gc |
| * -Xmx500m -XX:G1HeapRegionSize=1m -XX:MaxGCPauseMillis=1000 TestMultiThreadStressRSet 600 32 |
| */ |
| public class TestMultiThreadStressRSet { |
| |
| private static final Random RND = new Random(2015 * 2016); |
| private static final WhiteBox WB = WhiteBox.getWhiteBox(); |
| private static final int REF_SIZE = WB.getHeapOopSize(); |
| private static final int REGION_SIZE = WB.g1RegionSize(); |
| |
| // How many regions to use for the storage |
| private static final int STORAGE_REGIONS = 20; |
| |
| // Size a single obj in the storage |
| private static final int OBJ_SIZE = 1024; |
| |
| // How many regions of young/old gen to use in the BUFFER |
| private static final int BUFFER_YOUNG_REGIONS = 60; |
| private static final int BUFFER_OLD_REGIONS = 40; |
| |
| // Total number of objects in the storage. |
| private final int N; |
| |
| // The storage of byte[] |
| private final List<Object> STORAGE; |
| |
| // Where references to the Storage will be stored |
| private final List<Object[]> BUFFER; |
| |
| // The length of a buffer element. |
| // RSet deals with "cards" (areas of 512 bytes), not with single refs |
| // So, to affect the RSet the BUFFER refs should be allocated in different |
| // memory cards. |
| private final int BUF_ARR_LEN = 100 * (512 / REF_SIZE); |
| |
| // Total number of objects in the young/old buffers |
| private final int YOUNG; |
| private final int OLD; |
| |
| // To cause Remembered Sets change their coarse level the test uses a window |
| // within STORAGE. All the BUFFER elements refer to only STORAGE objects |
| // from the current window. The window is defined by a range. |
| // The first element has got the index: 'windowStart', |
| // the last one: 'windowStart + windowSize - 1' |
| // The window is shifting periodically. |
| private int windowStart; |
| private final int windowSize; |
| |
| // Counter of created worker threads |
| private int counter = 0; |
| |
| private volatile String errorMessage = null; |
| private volatile boolean isEnough = false; |
| |
| public static void main(String args[]) { |
| if (args.length != 2) { |
| throw new IllegalArgumentException("TEST BUG: wrong arg count " + args.length); |
| } |
| long time = Long.parseLong(args[0]); |
| int threads = Integer.parseInt(args[1]); |
| new TestMultiThreadStressRSet().test(time * 1000, threads); |
| } |
| |
| /** |
| * Initiates test parameters, fills out the STORAGE and BUFFER. |
| */ |
| public TestMultiThreadStressRSet() { |
| |
| N = (REGION_SIZE - 1) * STORAGE_REGIONS / OBJ_SIZE + 1; |
| STORAGE = new ArrayList<>(N); |
| int bytes = OBJ_SIZE - 20; |
| for (int i = 0; i < N - 1; i++) { |
| STORAGE.add(new byte[bytes]); |
| } |
| STORAGE.add(new byte[REGION_SIZE / 2 + 100]); // humongous |
| windowStart = 0; |
| windowSize = REGION_SIZE / OBJ_SIZE; |
| |
| BUFFER = new ArrayList<>(); |
| int sizeOfBufferObject = 20 + REF_SIZE * BUF_ARR_LEN; |
| OLD = REGION_SIZE * BUFFER_OLD_REGIONS / sizeOfBufferObject; |
| YOUNG = REGION_SIZE * BUFFER_YOUNG_REGIONS / sizeOfBufferObject; |
| for (int i = 0; i < OLD + YOUNG; i++) { |
| BUFFER.add(new Object[BUF_ARR_LEN]); |
| } |
| } |
| |
| /** |
| * Does the testing. Steps: |
| * <ul> |
| * <li> starts the Shifter thread |
| * <li> during the given time starts new Worker threads, keeping the number |
| * of live thread under limit. |
| * <li> stops the Shifter thread |
| * </ul> |
| * |
| * @param timeInMillis how long to stress |
| * @param maxThreads the maximum number of Worker thread working together. |
| */ |
| public void test(long timeInMillis, int maxThreads) { |
| if (timeInMillis <= 0 || maxThreads <= 0) { |
| throw new IllegalArgumentException("TEST BUG: be positive!"); |
| } |
| System.out.println("%% Time to work: " + timeInMillis / 1000 + "s"); |
| System.out.println("%% Number of threads: " + maxThreads); |
| long finish = System.currentTimeMillis() + timeInMillis; |
| Shifter shift = new Shifter(this, 1000, (int) (windowSize * 0.9)); |
| shift.start(); |
| for (int i = 0; i < maxThreads; i++) { |
| new Worker(this, 100).start(); |
| } |
| try { |
| while (System.currentTimeMillis() < finish && errorMessage == null) { |
| Thread.sleep(100); |
| } |
| } catch (Throwable t) { |
| printAllStackTraces(System.err); |
| t.printStackTrace(System.err); |
| this.errorMessage = t.getMessage(); |
| } finally { |
| isEnough = true; |
| } |
| System.out.println("%% Total work cycles: " + counter); |
| if (errorMessage != null) { |
| throw new RuntimeException(errorMessage); |
| } |
| } |
| |
| /** |
| * Returns an element from from the BUFFER (an object array) to keep |
| * references to the storage. |
| * |
| * @return an Object[] from buffer. |
| */ |
| private Object[] getFromBuffer() { |
| int index = counter % (OLD + YOUNG); |
| synchronized (BUFFER) { |
| if (index < OLD) { |
| if (counter % 100 == (counter / 100) % 100) { |
| // need to generate garbage in the old gen to provoke mixed GC |
| return replaceInBuffer(index); |
| } else { |
| return BUFFER.get(index); |
| } |
| } else { |
| return replaceInBuffer(index); |
| } |
| } |
| } |
| |
| private Object[] replaceInBuffer(int index) { |
| Object[] objs = new Object[BUF_ARR_LEN]; |
| BUFFER.set(index, objs); |
| return objs; |
| } |
| |
| /** |
| * Returns a random object from the current window within the storage. |
| * A storage element with index from windowStart to windowStart+windowSize. |
| * |
| * @return a random element from the current window within the storage. |
| */ |
| private Object getRandomObject() { |
| int index = (windowStart + RND.nextInt(windowSize)) % N; |
| return STORAGE.get(index); |
| } |
| |
| private static void printAllStackTraces(PrintStream ps) { |
| Map<Thread, StackTraceElement[]> traces = Thread.getAllStackTraces(); |
| for (Thread t : traces.keySet()) { |
| ps.println(t.toString() + " " + t.getState()); |
| for (StackTraceElement traceElement : traces.get(t)) { |
| ps.println("\tat " + traceElement); |
| } |
| } |
| } |
| |
| /** |
| * Thread to create a number of references from BUFFER to STORAGE. |
| */ |
| private static class Worker extends Thread { |
| |
| final TestMultiThreadStressRSet boss; |
| final int refs; // number of refs to OldGen |
| |
| /** |
| * @param boss the tests |
| * @param refsToOldGen how many references to the OldGen to create |
| */ |
| Worker(TestMultiThreadStressRSet boss, int refsToOldGen) { |
| this.boss = boss; |
| this.refs = refsToOldGen; |
| } |
| |
| @Override |
| public void run() { |
| try { |
| while (!boss.isEnough) { |
| Object[] objs = boss.getFromBuffer(); |
| int step = objs.length / refs; |
| for (int i = 0; i < refs; i += step) { |
| objs[i] = boss.getRandomObject(); |
| } |
| boss.counter++; |
| } |
| } catch (Throwable t) { |
| t.printStackTrace(System.out); |
| boss.errorMessage = t.getMessage(); |
| } |
| } |
| } |
| |
| /** |
| * Periodically shifts the current STORAGE window, removing references |
| * in BUFFER that refer to objects outside the window. |
| */ |
| private static class Shifter extends Thread { |
| |
| final TestMultiThreadStressRSet boss; |
| final int sleepTime; |
| final int shift; |
| |
| Shifter(TestMultiThreadStressRSet boss, int sleepTime, int shift) { |
| this.boss = boss; |
| this.sleepTime = sleepTime; |
| this.shift = shift; |
| } |
| |
| @Override |
| public void run() { |
| try { |
| while (!boss.isEnough) { |
| Thread.sleep(sleepTime); |
| boss.windowStart += shift; |
| for (int i = 0; i < boss.OLD; i++) { |
| Object[] objs = boss.BUFFER.get(i); |
| for (int j = 0; j < objs.length; j++) { |
| objs[j] = null; |
| } |
| } |
| if (!WB.g1InConcurrentMark()) { |
| System.out.println("%% start CMC"); |
| WB.g1StartConcMarkCycle(); |
| } else { |
| System.out.println("%% CMC is already in progress"); |
| } |
| } |
| } catch (Throwable t) { |
| t.printStackTrace(System.out); |
| boss.errorMessage = t.getMessage(); |
| } |
| } |
| } |
| } |
| |