有没有办法全面了解进程分配的所有内存？

Question

首先是一些背景故事。我有一个基本视图，由我的应用程序的三个主要视图扩展。子视图是空的、模拟的和数字的。我将这些子视图放入网格视图（2x3）中，并将网格视图放入滑动绘图中。这个滑动抽屉是我的应用程序的关键。这是绝对必要的。滑动抽屉必须存在于每个活动中，因此当活动发生变化时，我只需将状态存储在应用程序中，并在新活动加载时检索它。

当应用程序打开时，gridview 创建六个空视图并将它们添加到其适配器中。现在，虽然所有视图都是空的，但应用程序可以完美运行。我可以浏览这些活动并执行该应用程序具有的所有其他功能。当我从事相同的活动时，我可以根据自己的喜好创建模拟和数字视图。他们移动、删除并正确执行所有功能。但是，一旦我切换到另一项活动并且，即使网格视图中有一个模拟或数字视图，应用程序也会因OutOfMemoryError：位图大小超出虚拟机预算而崩溃。

模拟视图和数字视图都会为自己创建两个位图。一个是视图的背景，另一个是视图的独特外观，很少发生变化，因此更适合作为位图。两个位图都相当小（在我的测试 Evo 上为 221x221 像素）。这让我觉得我没有在活动变化时正确地回收它们。所以我回去检查所有东西是否都被清理干净，并制定了一个方法来完全破坏每个视图。每个变量都设置为 null，并且当活动暂停时，所有位图都会被回收。 （注意：使用记录器，我验证了 onPause 以及我的 destroy 方法确实被调用。）

现在 - 几天后 - 我仍然无法弄清楚为什么会抛出这个内存错误。我花了不计其数的时间查看 DDMS 和内存跟踪器，它很可能是有史以来最无用的东西。我完全厌倦了 DDMS，我无法让愚蠢的东西告诉我任何有用的东西。

那么现在问题来了。有没有一种方法（方法/系统调用或其他方法）可以让我获取进程（我的应用程序）分配的完整列表并打印/显示/保存到文件/等...？

编辑1：这是对Falmarri的回应。我可能发布的内容有点太多，对此我深表歉意。如果您想查看更具体的内容，我非常乐意提供帮助，您没有理由撕毁我的代码。

剪辑来自 BaseView：

public abstract class GaugeBase extends View implements BroadcastListener {
    protected static final String TAG = "GaugeBase";
    // =======================================
    // --- Declarations 
    /** Animation dynamics. */
    protected float mTarget = 0, position = 0, velocity = 0.0f, acceleration = 0.0f;
    protected long lastMoveTime = -1L;

    /** Background objects. */
    protected Bitmap mBackground;
    protected Bitmap mFaceTexture;
    protected float borderSize = 0.02f;

    /** Face objects. */
    protected Paint mRimShadowPaint, mTitlePaint, mFacePaint, mRimPaint, mRimBorderPaint;
    protected Path mTitlePath;

    /** Bounding rects. */
    protected static RectF mRimRect, mFaceRect;

    /** Text tools. */
    protected static Typeface mTypeface;

    /** The preferred size of the widget. */
    private static final int mPreferredSize = 300;

    /** The Broadcaster the gauge is registered to. */
    protected SensorBroadcaster mCaster;

    /** Is the view instantiated? */
    private boolean isDestroyed = true;
    // ---
    // =======================================

    public GaugeBase(Context context) {
        super(context);
        mCaster = ((AppionApplication)getContext().getApplicationContext())
            .getSensorBroadcaster(AppionApplication.TEST_SENSOR);
        lastMoveTime = System.currentTimeMillis();
        setTarget(mCaster.getReading());
    }

    @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); }
    @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); }
    @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { regenerate(); } 
    @Override public void onBroadcastReceived() { setTarget(mCaster.getReading()); }

    @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
        int chosenWidth = chooseDimension(widthMode, widthSize);
        int chosenHeight = chooseDimension(heightMode, heightSize);
        int chosenDimension = Math.min(chosenWidth, chosenHeight);
        setMeasuredDimension(chosenDimension, chosenDimension);
    }
    @Override protected void onDraw(Canvas canvas) {
        if (isDestroyed) return;
        if (mBackground == null) regenerate(); 
        canvas.drawBitmap(mBackground, 0, 0, null);
        canvas.save(Canvas.MATRIX_SAVE_FLAG);
        canvas.scale((float)getWidth(), (float)getWidth());
        drawForeground(canvas); canvas.restore(); animate();
    }

    public HashMap<String, Object> onSavePersistentState() {
        HashMap<String, Object> mState = new HashMap<String, Object>();
        mState.put("sensor_broadcaster", mCaster.getBroadcasterName());
        mState.put("type", this.getClass().getSimpleName());
        return mState;
    }

    public void onRestorePersistentState(HashMap<String, Object> state) {
        mCaster = ((AppionApplication)getContext().getApplicationContext())
            .getSensorBroadcaster((String)state.get("sensor_broadcaster"));
    }

    private final void setTarget(float target) { mTarget = target; animate(); }

    private static final int chooseDimension(int mode, int size) {
        if (mode == MeasureSpec.AT_MOST || mode == MeasureSpec.EXACTLY) return size;
        else return mPreferredSize;
    }

    private final void animate() {
        if (! (Math.abs(position - mTarget) > 0.01f)) return;
        if (lastMoveTime != -1L) {
            long currentTime = System.currentTimeMillis();
            float delta = (currentTime - lastMoveTime) / 1000.0f;
            float direction = Math.signum(velocity);
            if (Math.abs(velocity) < 90.0f) acceleration = 10.0f * (mTarget - position);
            else acceleration = 0.0f;
            position += velocity * delta;
            velocity += acceleration * delta;
            if ((mTarget - position) * direction < 0.01f * direction) {
                position = mTarget;
                velocity = 0.0f;
                acceleration = 0.0f;
                lastMoveTime = -1L;
            } else lastMoveTime = System.currentTimeMillis();               
            invalidate();
        } else {
            lastMoveTime = System.currentTimeMillis();
            animate();
        }
    }

    public void preInit() {
        mTypeface = Typeface.createFromAsset(getContext().getAssets(),
                "fonts/SFDigitalReadout-Heavy.ttf");
        mFaceTexture = BitmapFactory.decodeResource(getContext().getResources(),
                R.drawable.gauge_face);
        BitmapShader shader = new BitmapShader(mFaceTexture, 
                Shader.TileMode.MIRROR, Shader.TileMode.MIRROR);

        Matrix matrix = new Matrix();
        mRimRect = new RectF(0.05f, 0.05f, 0.95f, 0.95f);
        mFaceRect = new RectF(mRimRect.left + borderSize, mRimRect.top + borderSize,
                             mRimRect.right - borderSize, mRimRect.bottom - borderSize);


        mFacePaint = new Paint();
        mFacePaint.setFilterBitmap(true);
        matrix.setScale(1.0f / mFaceTexture.getWidth(), 1.0f / mFaceTexture.getHeight());
        shader.setLocalMatrix(matrix);
        mFacePaint.setStyle(Paint.Style.FILL);
        mFacePaint.setShader(shader);

        mRimShadowPaint = new Paint();
        mRimShadowPaint.setShader(new RadialGradient(0.5f, 0.5f, mFaceRect.width() / 2.0f,
                new int[] { 0x00000000, 0x00000500, 0x50000500 },
                new float[] { 0.96f, 0.96f, 0.99f },
                Shader.TileMode.MIRROR));
        mRimShadowPaint.setStyle(Paint.Style.FILL);

        mRimPaint = new Paint();
        mRimPaint.setFlags(Paint.ANTI_ALIAS_FLAG);
        mRimPaint.setShader(new LinearGradient(0.4f, 0.6f, 0.6f, 1.0f,
                Color.rgb(0xff0, 0xf5, 0xf0), Color.rgb(0x30, 0x31, 0x30),
                Shader.TileMode.CLAMP));

        mRimBorderPaint = new Paint();
        mRimBorderPaint.setAntiAlias(true);
        mRimBorderPaint.setStyle(Paint.Style.STROKE);
        mRimBorderPaint.setColor(Color.argb(0x4f, 0x33, 0x36, 0x33));
        mRimBorderPaint.setStrokeWidth(0.005f);

        mTitlePaint = new Paint();
        mTitlePaint.setColor(0xff000000);
        mTitlePaint.setAntiAlias(true);
        mTitlePaint.setTypeface(mTypeface);
        mTitlePaint.setTextAlign(Paint.Align.CENTER);
        mTitlePaint.setTextSize(0.2f);
        mTitlePaint.setTextScaleX(0.8f);        

        // Now we prepare the gauge
        init();
        isDestroyed = false;
    }

    /** Update the gauge independent static buffer cache for the background. */
    private void regenerate() {
        if (isDestroyed) return;
        if(mBackground != null) { mBackground.recycle(); mBackground = null; } 
        // Our new drawing area
        mBackground = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
        Canvas backCanvas = new Canvas(mBackground);
        float scale = (float)getWidth();
        backCanvas.scale(scale, scale);
        drawRim(backCanvas);
        drawFace(backCanvas);
        drawTitle(backCanvas);
        if (!(this instanceof EmptySpace)) { mCaster.getGroup().draw(backCanvas); }
        regenerateBackground(backCanvas);
    }

    /** Prepare the view to be cleaned up. This is called to prevent memory leaks. */
    public void destroy() { 
        isDestroyed = true;
        if (mFaceTexture != null) { mFaceTexture.recycle(); mBackground = null; }
        if (mBackground != null) { mBackground.recycle(); mBackground = null; }
        mRimShadowPaint = null;
        mRimShadowPaint = null;
        mFacePaint = null;
        mRimPaint = null;
        mRimBorderPaint = null;
        mTitlePath = null;
        mRimRect = null; mFaceRect = null;
        mTypeface = null;
        destroyDrawingCache();
    }

    /**
     * Create a bitmap of the gauge. The bitmap is to scale. 
     * @return The bitmap of the gauge.
     */
    int tobitmap = 0;
    public Bitmap toBitmap() {
        Bitmap b = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas();
        canvas.setBitmap(b);
        draw(canvas);
        return b;
    }

    /** Update the gauge dependent static buffer cache for the background. */
    protected abstract void regenerateBackground(Canvas canvas);
    /** Initializes all of the objects the gauge widget will need before use. */
    protected abstract void init();
    /** This is called when drawing the background. Draws the bordered edge of the gauge. */
    protected abstract void drawRim(Canvas canvas);
    /** This is called when drawing the background. Draws the face of the gauge. */
    protected abstract void drawFace(Canvas canvas);
    /** This is called when drawing the background. Draws the title to the gauge. */
    protected abstract void drawTitle(Canvas canvas);
    /**
     *  This is called when drawing the foreground. The foreground includes items like the 
     *  scale of an analog gauge, or the text of a digital gauge. Also any other necessary
     *  items that need drawing go here. Note: drawForeground is called quickly, repeatedly, 
     *  make it run fast and clean.
     */
    protected abstract void drawForeground(Canvas canvas);
}

这是来自数字视图：（因为它较小，但仍然会导致错误）

public class DigitalGauge extends GaugeBase {
    // ================================
    // --- Drawing tools
    private RectF lcdRect;
    private Paint lcdPaint, detailPaint;
    private Path facePath, borderPath;
    // ---
    // ================================
    public DigitalGauge(Context context) {
        super(context);
    }

    @Override protected void regenerateBackground(Canvas canvas) { }
    @Override protected void init() {
        lcdPaint = new Paint();
        lcdPaint.setColor(0xff000000);
        lcdPaint.setAntiAlias(true);
        lcdPaint.setStrokeWidth(0.005f);
        lcdPaint.setTextSize(0.4f);
        lcdPaint.setTypeface(mTypeface);
        lcdPaint.setTextAlign(Paint.Align.CENTER);

        detailPaint = new Paint();
        detailPaint.setColor(0xff000000);
        detailPaint.setTextSize(0.2f);
        detailPaint.setStrokeWidth(0.005f);
        detailPaint.setAntiAlias(true);
        detailPaint.setTypeface(mTypeface);
        detailPaint.setTextScaleX(0.8f);
        detailPaint.setTextAlign(Paint.Align.CENTER);

        facePath = new Path();
        facePath.moveTo(0.12f, 0.0f);
        facePath.lineTo(0.88f, 0.0f);
        facePath.arcTo(new RectF(), 0, 90);
        // TODO Make the trapazoidal look of the digital gauge


        lcdRect = new RectF(mFaceRect.left + borderSize, mFaceRect.top + borderSize,
                mFaceRect.right - borderSize, mFaceRect.top - borderSize - lcdPaint.getTextSize());
    }

    @Override protected void drawRim(Canvas canvas) {
        canvas.drawRect(mRimRect, mRimPaint);
        canvas.drawRect(mRimRect, mRimBorderPaint);
    }

    @Override protected void drawFace(Canvas canvas) {
        canvas.drawRect(mFaceRect, mFacePaint);
        canvas.drawRect(mFaceRect, mRimBorderPaint);
    }

    @Override protected void drawTitle(Canvas canvas) {
        canvas.drawText(mCaster.getBroadcasterSerial(), mFaceRect.left - 0.1f,
                mFaceRect.top + 0.1f, mTitlePaint);
    }
    @Override protected void drawForeground(Canvas canvas) {
        String display = "000000" + String.valueOf(Math.ceil(position));
        String read = display.substring(display.length()-8, display.length() - 2);
        canvas.drawText(read, 0.5f, lcdRect.top + lcdPaint.getTextSize() / 2, lcdPaint);
        /**canvas.drawText(mContext.getResources().getStringArray(R.array.pressureTypes)[measurement],
            0.5f, lcdRect.top + lcdPaint.getTextSize() , detailPaint);*/
    }
}

至于通过应用程序传递的状态，我将视图类型和视图所代表的caster的字符串名称放入其中哈希图。我将该哈希图传递给 gridview，然后将所有六个映射放入一个数组中，该数组将表示 gridview 中视图的位置。然后该数组保存在应用程序中并根据需要进行检索。

这是网格视图。我越想越觉得这堂课可能是问题所在。

public class Workbench extends GridView {
    /** Our debugging tag */
    private static final String TAG = "Workbench";
    /** Name of the Workbench. */
    private String mId = "-1";
    /** The title of the Workbench. */
    private String mTitle = "Workbench";
    /** The list of Widgets that will be handled by the bench */
    private GaugeBase[] mContent = new GaugeBase[6];
    /** The current selection from the bench */
    private int mSelection = -1;

    /** When a GaugeBase is moves we want to remove from the adapter. Now we won't lose it.*/
    private GaugeBase mHeldGaugeBase = null;
    private Bitmap mHold = null;
    private boolean mIsHolding = false;
    private float x = -1000f, y = -1000f; // Where the held bitmap should be
    private Bitmap trash;
    private RectF trashBox;

    // The touch listener we will use if we need to move a widget around
    private OnTouchListener mWidgetExchanger = new OnTouchListener() {
        @Override public boolean onTouch(View v, MotionEvent e) {
            int w = getWidth(); int h = getHeight(); 
            float xx = e.getX(); float yy = e.getY();
            switch (e.getAction()) {
            case MotionEvent.ACTION_DOWN: // Fall through
            case MotionEvent.ACTION_MOVE: 
                if (mIsHolding) {
                    x = e.getX() - mHold.getWidth()/2; y = e.getY() - mHold.getHeight()/2;
                    postInvalidate(); break;
                }
            case MotionEvent.ACTION_UP: 
                if (mIsHolding) {
                    if (trashBox.contains(xx, yy)) removeGaugeBase(mSelection);
                    else {
                        if ((xx < w / 2) && (yy < h /3)) makeSwitch(0);
                        else if ((xx > w / 2) && (yy < h /3)) makeSwitch(1);
                        else if ((xx < w / 2) && (yy > h /3) && (yy < h * .666)) makeSwitch(2);
                        else if ((xx > w / 2) && (yy > h /3) && (yy < h * .666)) makeSwitch(3);
                        else if ((xx < w / 2) && (yy > h *.666)) makeSwitch(4);
                        else if ((xx > w / 2) && (yy > h *.666)) makeSwitch(5);
                    }
                    mSelection = -1;
                    //mHeldGaugeBase.destroy(); mHeldGaugeBase = null;
                    mHold.recycle(); mHold = null;
                    trash.recycle(); trash = null;
                    mIsHolding = false;
                    setOnTouchListener(null);
                    x = -1000f; y = -1000f;
                    ((AppionApplication)getContext().getApplicationContext()).vibrate(200); update();
                }
                break;
            }
            return true;
        }
    };

    public Workbench(Context context) { this(context, null); }
    public Workbench(Context context, AttributeSet attrs) { this(context, attrs, 0); }
    public Workbench(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        for (int i = 0; i < mContent.length; i++) {
            mContent[i] = new EmptySpace(getContext());
        }
        setAdapter(new BenchAdapter());
        this.setOnItemClickListener(new OnItemClickListener() {
            @Override public void onItemClick(AdapterView<?> arg0, View view, final int pos, long arg3) {
                if (mContent[pos] instanceof EmptySpace) {
                    CharSequence[] items = {"Analog", "Digital"};
                    AlertDialog.Builder adb = new AlertDialog.Builder(getContext());
                        adb.setTitle("Add a widget?")
                            .setItems(items, new DialogInterface.OnClickListener () {
                                @Override public void onClick(DialogInterface arg0, int position) {
                                    mContent[pos].destroy();
                                    mContent[pos] = null;
                                    SensorBroadcaster s = ((AppionApplication)getContext().getApplicationContext()).
                                        getSensorBroadcaster(AppionApplication.TEST_SENSOR);
                                    switch (position) {
                                    case 0: // Add an Analog GaugeBase to the Workbench
                                        mContent[pos] = new AnalogGauge(getContext());
                                        // TODO: Option to link to a manager
                                        break;
                                    case 1: // Add a digital GaugeBase to the Workbench
                                        mContent[pos] = new DigitalGauge(getContext());
                                        // TODO: Option to link to a manager
                                        break;
                                    } mContent[pos].preInit();
                                    update();
                                }
                            });
                        adb.show();
                } //else new GaugeBaseDialog(getContext(), Workbench.this, (GaugeBase)view, pos).show();
            }
        });
        setOnItemLongClickListener(new OnItemLongClickListener() {
            @Override public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
                    int pos, long arg3) {
                mSelection = pos;
                mHold = mContent[pos].toBitmap();
                mHeldGaugeBase = mContent[pos];
                mHeldGaugeBase.destroy();
                trash = Bitmap.createScaledBitmap(BitmapFactory.decodeResource(getContext().getResources(),
                        R.drawable.trash), getWidth() / 10, getHeight() / 10, true);
                trashBox = new RectF(getWidth() / 2 - trash.getWidth()/2, getHeight() - trash.getHeight(),
                        getWidth() /2 + trash.getWidth() /2, getHeight());
                mContent[pos] = new EmptySpace(getContext());
                update();
                mIsHolding = true;
                setOnTouchListener(mWidgetExchanger);
                ((AppionApplication)getContext().getApplicationContext()).vibrate(300);
                return false;
            }
        });
    }

    /**
     * Perform a switch in within the bench. Exchange on slot with another.
     * @param slot The slot of the widgets list that we are switching to.
     */
    public void makeSwitch(int slot) {
        if (mSelection == -1) return;
        Log.i(TAG, "Performing a Widget switch");
        mContent[mSelection].destroy();
        mContent[mSelection] = mContent[slot];
        mContent[slot] = mHeldGaugeBase;
        mContent[slot].preInit();
        mContent[slot].invalidate();
        Log.d(TAG, " mSelection = " + mContent[mSelection] + " slot = " +mContent[slot]);
        update();                                                               
    }

Answer 1

这是对 @mah 的回应，但评论太长了。

它总是以倍数执行
系统页面大小

这不一定是真的。尤其是使用 Android 应用程序。有许多不同的内存分配器具有不同的语义。然而，假设您谈论的是JAVA，而不是 NDK (C++)，那么透明度就更低了。 Java 的虚拟机（或者更确切地说，dalvik）几乎肯定会在机器启动时过度分配内存，然后当应用程序请求少量内存时，它会从该池中将其提供给您。

如果它的池中的内存不足，它将从操作系统分配另一个块并将其添加到其池中并从那里返回一个块。

但是，如果您请求大内存块，例如您想要位图，JVM（或 dalvik 机器）很可能会使用系统的 mmap 方法，该方法映射一部分内存。根据具体情况，它可以制作私人匿名地图，然后让您访问其中的各个部分。或者，它可以将文件映射到内存中，这基本上是磁盘上内容的内存视图。这可能就是 dalvic 处理大位图分配的方式。

并提出了一种完全
销毁每个视图

首先，您实际上无法直接控制 java 中的视图。将对象设置为 null 并不会删除它。即使您假设只有对该对象的单个引用，您也必须等到垃圾收集器清理该对象的数据。

---

确实不可能告诉你你的问题是什么，甚至连一个提示也不可能。我真正能说的是，您可能在比您想象的更多的地方为位图分配空间。或者您将对它们的引用保存在未清理的地方。

我只是将状态存储在
应用程序并在以下情况下检索它
新活动加载。

这是相当模糊的，但我首先看看你在这方面做了什么。比如说，如果您将位图作为可解析对象传递，则可能会根据需要分配 3-4 倍的空间。通过可解析接口发送大型自定义对象和位图非常昂贵。

我会建议以下几件事之一。您可以延迟加载位图。也就是说，永远不要将它们存储在任何地方。仅在需要时将其拉起。这可能是一个解决方案，因为它可能是您认为自己比编译器更聪明的情况。但我保证编译器在高效内存使用方面比你更聪明。

--

或者，您可以尝试相反的方法，仅在应用程序加载时加载位图，并确保每次显示它时，您不会创建新的位图或任何内容。这样它只会在内存中存在一次，如果它确实太大，你就会很早就崩溃并在一个已知的地方。

--

最后，如果您确实找不到解决方案，并且您确实认为您的 java 进程确实内存不足，您可以重写 NDK 中处理位图视图的部分。这样，如果您没有明确执行此操作，它们就不会被垃圾收集和重新创建。

--

现在问题来了。有办法吗
（方法/系统调用什么的）
我可以获得完整的列表
进程的分配（我的应用程序）和
打印/显示/保存到文件/
等等...它？

我确信有。但是，这是一个很大的但是，它无论如何都不会容易。您可能需要做的就是用跟踪谁请求内存的版本替换系统的 glibc（即专门的 malloc 函数）。然而，即使这样也会被java虚拟机混淆。

---

长话短说，发布一些代码，尤其是操作和保存视图和位图的部分。

更新：

只要浏览一下您的代码，我就会检查 regenerate() 被调用的频率，特别是因为：

mBackground = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
Canvas backCanvas = new Canvas(mBackground);

我不是 java 位图内存方面的专家管理，但我的猜测是这会很昂贵。

Answer 2

我建议您观看此视频。
它在很多方面帮助了我，而且我也遇到了位图大小和虚拟机内存预算的问题。

根据我的经验：我养成了在 .recycle() 之后到处调用 System.gc() 的坏习惯。我知道这不好，但它帮助我防止了这种强制关闭，经过几个小时的调试为什么我的位图没有正确回收。

Answer 3

您可以查看 /proc/self/maps （在进程内）或 /proc/[process id]/maps，但这不太可能告诉您您想要什么，并且没有系统调用会告诉您。当您在进程中分配内存时，即使您只分配 1 个字节，它也始终以系统页面大小的倍数（4kb，也许更多）执行 - 但它随后会在内部进行管理。在从系统接收更多内存之前，未来的分配来自该块。