8132715: Add tests which check that no allocations allowed in any of humongous regions
Reviewed-by: dfazunen, tschatzl
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/gc/g1/humongousObjects/TestNoAllocationsInHRegions.java Wed Jun 29 17:01:55 2016 +0300
@@ -0,0 +1,234 @@
+/*
+ * 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.
+ *
+ */
+
+package gc.g1.humongousObjects;
+
+import jdk.test.lib.Utils;
+import sun.hotspot.WhiteBox;
+
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Random;
+import java.util.stream.Collectors;
+
+/**
+ * @test TestNoAllocationsInHRegions
+ * @summary Checks that no additional allocations are made in humongous regions
+ * @requires vm.gc.G1
+ * @library /testlibrary /test/lib /
+ * @modules java.management java.base/jdk.internal.misc
+ * @build sun.hotspot.WhiteBox
+ * gc.testlibrary.Helpers
+ * gc.g1.humongousObjects.TestNoAllocationsInHRegions
+ *
+ * @run driver ClassFileInstaller sun.hotspot.WhiteBox
+ * sun.hotspot.WhiteBox$WhiteBoxPermission
+ *
+ * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0
+ * -Xlog:gc=trace:file=TestNoAllocationsInHRegions10.log
+ * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 10
+ *
+ * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0
+ * -Xlog:gc=trace:file=TestNoAllocationsInHRegions50.log
+ * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 50
+ *
+ * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0
+ * -Xlog:gc=trace:file=TestNoAllocationsInHRegions70.log
+ * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 70
+ */
+public class TestNoAllocationsInHRegions {
+ private static final WhiteBox WB = WhiteBox.getWhiteBox();
+ private static final Random RND = Utils.getRandomInstance();
+ private static final int G1_REGION_SIZE = WB.g1RegionSize();
+ private static final int[] HUMONGOUS_SIZES = {G1_REGION_SIZE / 2, G1_REGION_SIZE + 1, G1_REGION_SIZE * 2 + 1};
+ private static final int ALLOC_THREAD_COUNT = 5;
+
+ // We fill specified part of heap with humongous objects - we need public static to prevent escape analysis to
+ // collect this field
+ public static LinkedList<byte[]> humongousAllocations = new LinkedList<>();
+
+ private static volatile boolean shouldStop = false;
+ private static volatile Error error = null;
+
+ static class Allocator implements Runnable {
+
+ private final List<byte[]> liveObjects = new LinkedList<>();
+ private int usedMemory = 0;
+ public final Runnable[] actions;
+
+ /**
+ * Maximum size of simple allocation
+ */
+ private static final int MAX_ALLOCATION_SIZE = (int) (G1_REGION_SIZE / 2 * 0.9);
+
+ /**
+ * Maximum size of dead (i.e. one which is made unreachable right after allocation) object
+ */
+ private static final int DEAD_OBJECT_MAX_SIZE = G1_REGION_SIZE / 10;
+
+ public Allocator(int maxAllocationMemory) {
+
+ actions = new Runnable[]{
+ // Allocation
+ () -> {
+ if (maxAllocationMemory - usedMemory != 0) {
+ int arraySize = RND.nextInt(Math.min(maxAllocationMemory - usedMemory,
+ MAX_ALLOCATION_SIZE));
+
+ if (arraySize != 0) {
+ byte[] allocation = new byte[arraySize];
+ liveObjects.add(allocation);
+ usedMemory += arraySize;
+
+ // Sanity check
+ if (WB.g1IsHumongous(allocation)) {
+ String errorMessage = String.format("Test Bug: Byte array of size"
+ + " %d is expected to be non-humongous but it is humongous",
+ allocation.length);
+
+ System.out.println(errorMessage);
+ error = new Error(errorMessage);
+ shouldStop = true;
+ }
+
+ // Test check
+ if (WB.g1BelongsToHumongousRegion(WB.getObjectAddress(allocation))) {
+ String errorMessage = String.format("Non-humongous allocation of byte array of "
+ + "length %d and size %d with address %d was made in Humongous Region",
+ allocation.length, WB.getObjectSize(allocation),
+ WB.getObjectAddress(allocation));
+
+ System.out.println(errorMessage);
+ error = new Error(errorMessage);
+ shouldStop = true;
+ }
+ }
+ }
+ },
+
+ // Deallocation
+ () -> {
+ if (liveObjects.size() != 0) {
+ int elementNum = RND.nextInt(liveObjects.size());
+ int shouldFree = liveObjects.get(elementNum).length;
+ liveObjects.remove(elementNum);
+ usedMemory -= shouldFree;
+ }
+ },
+
+ // Dead object allocation
+ () -> {
+ int size = RND.nextInt(DEAD_OBJECT_MAX_SIZE);
+ byte[] deadObject = new byte[size];
+ },
+
+ // Check
+ () -> {
+ List<byte[]> wrongHumongousAllocations = liveObjects.stream()
+ .filter(WB::g1IsHumongous)
+ .collect(Collectors.toList());
+
+ if (wrongHumongousAllocations.size() > 0) {
+ wrongHumongousAllocations.stream().forEach(a ->
+ System.out.format("Non-humongous allocation of byte array of length %d and"
+ + " size %d with address %d was made in Humongous Region",
+ a.length, WB.getObjectSize(a), WB.getObjectAddress(a)));
+ error = new Error("Some non-humongous allocations were made to humongous region");
+ shouldStop = true;
+ }
+ }
+ };
+ }
+
+ @Override
+ public void run() {
+ while (!shouldStop) {
+ actions[RND.nextInt(actions.length)].run();
+ Thread.yield();
+ }
+ }
+ }
+
+ public static void main(String[] args) {
+ if (args.length != 2) {
+ throw new Error("Test Bug: Expected duration (in seconds) and percent of allocated regions were not "
+ + "provided as command line argument");
+ }
+
+ // test duration
+ long duration = Integer.parseInt(args[0]) * 1000L;
+ // part of heap preallocated with humongous objects (in percents)
+ int percentOfAllocatedHeap = Integer.parseInt(args[1]);
+
+ long startTime = System.currentTimeMillis();
+
+ long initialFreeRegionsCount = WB.g1NumFreeRegions();
+ int regionsToAllocate = (int) ((double) initialFreeRegionsCount / 100.0 * percentOfAllocatedHeap);
+ long freeRegionLeft = initialFreeRegionsCount - regionsToAllocate;
+
+ System.out.println("Regions to allocate: " + regionsToAllocate + "; regions to left free: " + freeRegionLeft);
+
+ int maxMemoryPerAllocThread = (int) ((Runtime.getRuntime().freeMemory() / 100.0
+ * (100 - percentOfAllocatedHeap)) / ALLOC_THREAD_COUNT * 0.5);
+
+ System.out.println("Using " + maxMemoryPerAllocThread / 1024 + "KB for each of " + ALLOC_THREAD_COUNT
+ + " allocation threads");
+
+ while (WB.g1NumFreeRegions() > freeRegionLeft) {
+ try {
+ humongousAllocations.add(new byte[HUMONGOUS_SIZES[RND.nextInt(HUMONGOUS_SIZES.length)]]);
+ } catch (OutOfMemoryError oom) {
+ //We got OOM trying to fill heap with humongous objects
+ //It probably means that heap is fragmented which is strange since the test logic should avoid it
+ System.out.println("Warning: OOM while allocating humongous objects - it likely means "
+ + "that heap is fragmented");
+ break;
+ }
+ }
+
+ System.out.println("Initial free regions " + initialFreeRegionsCount + "; Free regions left "
+ + WB.g1NumFreeRegions());
+
+ LinkedList<Thread> threads = new LinkedList<>();
+
+ for (int i = 0; i < ALLOC_THREAD_COUNT; i++) {
+ threads.add(new Thread(new Allocator(maxMemoryPerAllocThread)));
+ }
+
+ threads.stream().forEach(Thread::start);
+
+ while ((System.currentTimeMillis() - startTime < duration) && error == null) {
+ Thread.yield();
+ }
+
+ shouldStop = true;
+ System.out.println("Finished test");
+ if (error != null) {
+ throw error;
+ }
+ }
+}