Java OutofMemory 奇怪的错误

Question

我已经使用以下命令从命令行启动了我的jar

java -Xms1200m -Xmx1500m -jar xxx.jar

我正在创建大小为 12600 * 12600 的 BufferedImage 意味着它需要

606 MB 以下代码中的内存

TranscoderInput input = new TranscoderInput(sr);

            String pngFile = "Style-" + shoeViewer.getCurrentStyle() + "_"
                    + shoeViewer.getSelectedMetadata().getSizeLabel()
                    + "_400DPI" + ".png";

            File outputFile = new File(pngFile);

            FileOutputStream fo = new FileOutputStream(outputFile);

            TranscoderOutput output = new TranscoderOutput(fo);

            long now = System.currentTimeMillis();

            t.transcode(input, null);

当我在执行以上行之前调试内存使用情况时，我的运行时显示

我需要 606 MB 内存，1100 MB 仍然可用。

因此，当我在 34 分钟后运行上面的代码时，它会抛出 OutOfMemory 异常。

问题是什么？是进程问题还是堆问题？为什么需要 34 分钟？？

我的电脑配置如下

Windows 32bit XP Service Pack2 Home Edition
Amd Athlon (tm) 7750 Dual Core 2.71 GHz
2GB of DDR2 RAM
java version "1.7.0_17"
Java(TM) SE Runtime Environment (build 1.7.0_17-b02)
Java HotSpot(TM) Client VM (build 23.7-b01, mixed mode, sharing)

请帮我解决这个问题。

下面是带有调试信息的异常栈tarce。

在运行上面的代码之前，我将 VM 参数更改为以下

java -Xms900m -Xmx1024m -XX:MinHeapFreeRatio=40 -XX:MaxHeapFreeRatio=70 -jar myjar.jar

从 SVG 阅读器构建 XML 文档.... 从 SVG 阅读器构建完成的 XML 文档.... 将修改后的 XML 文档转换为字符串编写器.... 修改后的 XML 文档到 String Writer 的转换完成.... claimedBytes 766 Avaialbel 字节 900189232 内存统计------------------------总内存为字节:912326656 总内存为兆字节:870已用内存为字节:9308384 已用内存为兆字节:8可用内存为字节:900189096 可用内存为兆字节:858

---

转码开始于:Sun Mar 24 11:09:59 IST 2013

Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap spa
ce
        at java.awt.image.DataBufferInt.<init>(Unknown Source)
        at java.awt.image.SinglePixelPackedSampleModel.createDataBuffer(Unknown
Source)
        at java.awt.image.Raster.createWritableRaster(Unknown Source)
        at org.apache.batik.gvt.renderer.StaticRenderer.updateWorkingBuffers(Sta
ticRenderer.java:536)
        at org.apache.batik.gvt.renderer.StaticRenderer.repaint(StaticRenderer.j
ava:375)
        at org.apache.batik.gvt.renderer.StaticRenderer.repaint(StaticRenderer.j
ava:344)
        at org.apache.batik.transcoder.image.ImageTranscoder.transcode(ImageTran
scoder.java:111)
        at org.apache.batik.transcoder.XMLAbstractTranscoder.transcode(XMLAbstra
ctTranscoder.java:142)
        at org.apache.batik.transcoder.SVGAbstractTranscoder.transcode(SVGAbstra
ctTranscoder.java:156)
        at com.mmg.app.eventlistener.PlaceOrderActionListener.save(PlaceOrderAct
ionListener.java:302)
        at com.mmg.app.eventlistener.PlaceOrderActionListener.saveCanvas(PlaceOr
derActionListener.java:270)
        at com.mmg.app.eventlistener.PlaceOrderActionListener.actionPerformed(Pl
aceOrderActionListener.java:143)
        at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
        at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
        at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
        at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Sour
ce)
        at java.awt.Component.processMouseEvent(Unknown Source)
        at javax.swing.JComponent.processMouseEvent(Unknown Source)
        at java.awt.Component.processEvent(Unknown Source)
        at java.awt.Container.processEvent(Unknown Source)
        at java.awt.Component.dispatchEventImpl(Unknown Source)
        at java.awt.Container.dispatchEventImpl(Unknown Source)
        at java.awt.Component.dispatchEvent(Unknown Source)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
        at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
        at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
        at java.awt.Container.dispatchEventImpl(Unknown Source)
        at java.awt.Window.dispatchEventImpl(Unknown Source)
        at java.awt.Component.dispatchEvent(Unknown Source)
        at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
        at java.awt.EventQueue.access$200(Unknown Source)

Answer 1

即使未编码的原始图像只能填充大约 600 MB，编码器中的内部表示也可能需要更多内存，具体取决于它的实现方式。以下示例显示将简单的 svg 文件缩放到 12600 x 12600(32 位)时使用了多少内存。

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.OutputStream;

import org.apache.batik.transcoder.TranscoderInput;
import org.apache.batik.transcoder.TranscoderOutput;
import org.apache.batik.transcoder.image.PNGTranscoder;

public class Test {
    public static void main(String[] args) throws Exception {
        PNGTranscoder t = new PNGTranscoder();
        t.addTranscodingHint(PNGTranscoder.KEY_WIDTH, new Float(12600));
        t.addTranscodingHint(PNGTranscoder.KEY_HEIGHT, new Float(12600));
        FileInputStream fis = new FileInputStream("C:\\StackOverflow\\SVG-logo.svg");
        TranscoderInput input = new TranscoderInput(fis);
        OutputStream ostream = new FileOutputStream("C:\\StackOverflow\\res.png");
        TranscoderOutput output = new TranscoderOutput(ostream);

        System.out.println("AllocatedMemory: \t" + (Runtime.getRuntime().totalMemory() / 1024) + " Kb");
        t.transcode(input, output);
        System.out.println("AllocatedMemory: \t" + (Runtime.getRuntime().totalMemory() / 1024) + " Kb");

        ostream.flush();
        ostream.close();

    }
}

在我的机器上输出是:

AllocatedMemory:    4096 Kb 
AllocatedMemory:    1677721 Kb

所以这里的程序使用 1677 MB 将一个简单的 SVG 文件转码为 12600 * 12600 PNG 文件。