| /* |
| * Copyright (C) 2009 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| import java.io.File; |
| import java.lang.ref.WeakReference; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.InvocationTargetException; |
| |
| public class Main { |
| public static volatile boolean quit = false; |
| public static final boolean DEBUG = false; |
| |
| private static final boolean WRITE_HPROF_DATA = false; |
| private static final int TEST_TIME = 10; |
| private static final String OUTPUT_FILE = "gc-thrash.hprof"; |
| |
| public static void main(String[] args) { |
| // dump heap before |
| |
| System.out.println("Running (" + TEST_TIME + " seconds) ..."); |
| runTests(); |
| |
| Method dumpHprofDataMethod = null; |
| String dumpFile = null; |
| |
| if (WRITE_HPROF_DATA) { |
| dumpHprofDataMethod = getDumpHprofDataMethod(); |
| if (dumpHprofDataMethod != null) { |
| dumpFile = getDumpFileName(); |
| System.out.println("Sending output to " + dumpFile); |
| } |
| } |
| |
| System.gc(); |
| System.runFinalization(); |
| System.gc(); |
| |
| if (WRITE_HPROF_DATA && dumpHprofDataMethod != null) { |
| try { |
| dumpHprofDataMethod.invoke(null, dumpFile); |
| } catch (IllegalAccessException iae) { |
| System.out.println(iae); |
| } catch (InvocationTargetException ite) { |
| System.out.println(ite); |
| } |
| } |
| |
| System.out.println("Done."); |
| } |
| |
| /** |
| * Finds VMDebug.dumpHprofData() through reflection. In the reference |
| * implementation this will not be available. |
| * |
| * @return the reflection object, or null if the method can't be found |
| */ |
| private static Method getDumpHprofDataMethod() { |
| ClassLoader myLoader = Main.class.getClassLoader(); |
| Class<?> vmdClass; |
| try { |
| vmdClass = myLoader.loadClass("dalvik.system.VMDebug"); |
| } catch (ClassNotFoundException cnfe) { |
| return null; |
| } |
| |
| Method meth; |
| try { |
| meth = vmdClass.getMethod("dumpHprofData", String.class); |
| } catch (NoSuchMethodException nsme) { |
| System.out.println("Found VMDebug but not dumpHprofData method"); |
| return null; |
| } |
| |
| return meth; |
| } |
| |
| private static String getDumpFileName() { |
| File tmpDir = new File("/tmp"); |
| if (tmpDir.exists() && tmpDir.isDirectory()) { |
| return "/tmp/" + OUTPUT_FILE; |
| } |
| |
| File sdcard = new File("/sdcard"); |
| if (sdcard.exists() && sdcard.isDirectory()) { |
| return "/sdcard/" + OUTPUT_FILE; |
| } |
| |
| return null; |
| } |
| |
| |
| /** |
| * Run the various tests for a set period. |
| */ |
| public static void runTests() { |
| Robin robin = new Robin(); |
| Deep deep = new Deep(); |
| Large large = new Large(); |
| |
| /* start all threads */ |
| robin.start(); |
| deep.start(); |
| large.start(); |
| |
| /* let everybody run for 10 seconds */ |
| sleep(TEST_TIME * 1000); |
| |
| quit = true; |
| |
| try { |
| /* wait for all threads to stop */ |
| robin.join(); |
| deep.join(); |
| large.join(); |
| } catch (InterruptedException ie) { |
| System.out.println("join was interrupted"); |
| } |
| } |
| |
| /** |
| * Sleeps for the "ms" milliseconds. |
| */ |
| public static void sleep(int ms) { |
| try { |
| Thread.sleep(ms); |
| } catch (InterruptedException ie) { |
| System.out.println("sleep was interrupted"); |
| } |
| } |
| |
| /** |
| * Sleeps briefly, allowing other threads some CPU time to get started. |
| */ |
| public static void startupDelay() { |
| sleep(500); |
| } |
| } |
| |
| |
| /** |
| * Allocates useless objects and holds on to several of them. |
| * |
| * Uses a single large array of references, replaced repeatedly in round-robin |
| * order. |
| */ |
| class Robin extends Thread { |
| private static final int ARRAY_SIZE = 40960; |
| int sleepCount = 0; |
| |
| public void run() { |
| Main.startupDelay(); |
| |
| String strings[] = new String[ARRAY_SIZE]; |
| int idx = 0; |
| |
| while (!Main.quit) { |
| strings[idx] = makeString(idx); |
| |
| if (idx % (ARRAY_SIZE / 4) == 0) { |
| Main.sleep(400); |
| sleepCount++; |
| } |
| |
| idx = (idx + 1) % ARRAY_SIZE; |
| } |
| |
| if (Main.DEBUG) |
| System.out.println("Robin: sleepCount=" + sleepCount); |
| } |
| |
| private String makeString(int val) { |
| try { |
| return new String("Robin" + val); |
| } catch (OutOfMemoryError e) { |
| return null; |
| } |
| } |
| } |
| |
| |
| /** |
| * Allocates useless objects in recursive calls. |
| */ |
| class Deep extends Thread { |
| private static final int MAX_DEPTH = 50; |
| |
| private static String strong[] = new String[MAX_DEPTH]; |
| private static WeakReference weak[] = new WeakReference[MAX_DEPTH]; |
| |
| public void run() { |
| int iter = 0; |
| boolean once = false; |
| |
| Main.startupDelay(); |
| |
| while (!Main.quit) { |
| dive(0, iter); |
| once = true; |
| iter += MAX_DEPTH; |
| } |
| |
| if (!once) { |
| System.out.println("not even once?"); |
| return; |
| } |
| |
| checkStringReferences(); |
| |
| /* |
| * Wipe "strong", do a GC, see if "weak" got collected. |
| */ |
| for (int i = 0; i < MAX_DEPTH; i++) |
| strong[i] = null; |
| |
| Runtime.getRuntime().gc(); |
| |
| for (int i = 0; i < MAX_DEPTH; i++) { |
| if (weak[i].get() != null) { |
| System.out.println("Deep: weak still has " + i); |
| } |
| } |
| |
| if (Main.DEBUG) |
| System.out.println("Deep: iters=" + iter / MAX_DEPTH); |
| } |
| |
| |
| /** |
| * Check the results of the last trip through. Everything in |
| * "weak" should be matched in "strong", and the two should be |
| * equivalent (object-wise, not just string-equality-wise). |
| * |
| * We do that check in a separate method to avoid retaining these |
| * String references in local DEX registers. In interpreter mode, |
| * they would retain these references until the end of the method |
| * or until they are updated to another value. |
| */ |
| private static void checkStringReferences() { |
| for (int i = 0; i < MAX_DEPTH; i++) { |
| if (strong[i] != weak[i].get()) { |
| System.out.println("Deep: " + i + " strong=" + strong[i] + |
| ", weak=" + weak[i].get()); |
| } |
| } |
| } |
| |
| /** |
| * Recursively dive down, setting one or more local variables. |
| * |
| * We pad the stack out with locals, attempting to create a mix of |
| * valid and invalid references on the stack. |
| */ |
| private String dive(int depth, int iteration) { |
| try { |
| String str0; |
| String str1; |
| String str2; |
| String str3; |
| String str4; |
| String str5; |
| String str6; |
| String str7; |
| String funStr = ""; |
| switch (iteration % 8) { |
| case 0: |
| funStr = str0 = makeString(iteration); |
| break; |
| case 1: |
| funStr = str1 = makeString(iteration); |
| break; |
| case 2: |
| funStr = str2 = makeString(iteration); |
| break; |
| case 3: |
| funStr = str3 = makeString(iteration); |
| break; |
| case 4: |
| funStr = str4 = makeString(iteration); |
| break; |
| case 5: |
| funStr = str5 = makeString(iteration); |
| break; |
| case 6: |
| funStr = str6 = makeString(iteration); |
| break; |
| case 7: |
| funStr = str7 = makeString(iteration); |
| break; |
| } |
| |
| weak[depth] = new WeakReference(funStr); |
| strong[depth] = funStr; |
| if (depth+1 < MAX_DEPTH) |
| dive(depth+1, iteration+1); |
| else |
| Main.sleep(100); |
| return funStr; |
| } catch (OutOfMemoryError e) { |
| // Silently ignore OOME since gc stress mode causes them to occur but shouldn't be a |
| // test failure. |
| } |
| return ""; |
| } |
| |
| private String makeString(int val) { |
| try { |
| return new String("Deep" + val); |
| } catch (OutOfMemoryError e) { |
| return null; |
| } |
| } |
| } |
| |
| |
| /** |
| * Allocates large useless objects. |
| */ |
| class Large extends Thread { |
| public void run() { |
| byte[] chunk; |
| int count = 0; |
| int sleepCount = 0; |
| |
| Main.startupDelay(); |
| |
| while (!Main.quit) { |
| try { |
| chunk = new byte[100000]; |
| pretendToUse(chunk); |
| |
| count++; |
| if ((count % 500) == 0) { |
| Main.sleep(400); |
| sleepCount++; |
| } |
| } catch (OutOfMemoryError e) { |
| } |
| } |
| |
| if (Main.DEBUG) |
| System.out.println("Large: sleepCount=" + sleepCount); |
| } |
| |
| public void pretendToUse(byte[] chunk) {} |
| } |