解决 java.lang.OutOfMemoryError：Java 堆空间

Question

正如标题所示，我在线程中遇到此错误。

违规的 LOC 如下所示：

for (int i = 0; i < objectListSize; i++) {
   logger.INFO("Loop repeat: "+i+" ...", true);
   final Double discreteScore = sp.getDouble(superPeerSocket);
   final int expectedObjectIDs = sp.getInteger(superPeerSocket);
   final String discreteObjects[] = new String[expectedObjectIDs];
   for ( int j = 0; j < expectedObjectIDs; j++)
      discreteObjects[j] = sp.getString(superPeerSocket);
   htPlus.attachInitialDiscreteList2L1(discreteScore, discreteObjects); 
}

The final String discreteObjects[] declaration is where I get the error. I am running this code inside a thread. I have two threads currently active when I get this. I also tried using the MAT tool from eclipse. here is a link with some chart files inside: PLC chart files (dropbox URL)
If anyone has any idea for this problem I would be grateful. P.S.: I am thinking to remove the loop although it just fails in the first loop pass.
(I get this in the output when the program fails)

Expected data size: 10
Repeat: 0 ...
java.lang.OutOfMemoryError: Java heap space
Dumping heap to java_pid3793.hprof ...
Heap dump file created [1404020 bytes in 0.015 secs]
Exception in thread "1" java.lang.OutOfMemoryError: Java heap space
    at planetlab.app.factory.Worker$15.run(Worker.java:796)
    at java.lang.Thread.run(Thread.java:662)

Something irrelevant:
What's with the code not properly formatted/intended error when making posts in stack overflow? It took me 15 minutes to figure out what to do :@ :S :@

Answer 1

每个 Java 程序都运行在沙箱中。虽然您的操作系统可能有 10 GB 可用 RAM，但您的应用程序可能只有 128 MB。

您需要使用 -Xms -Xmx 参数确保您的应用程序有足够的内存分配给 JVM。 -Xms 表示最小值，-Xmx 表示最大值

评论中建议您的预期ObjectID 似乎有点高。我当然会检查一下。但是，您可以使用以下代码来了解内存使用情况和可用内存。使用该信息，您可以相应地调整您的 -Xms -Xmx 。

祝你好运！

Runtime runtime = Runtime.getRuntime();  

long maxMemory = runtime.maxMemory();  
long allocatedMemory = runtime.totalMemory();  
long freeMemory = runtime.freeMemory();  

System.out.println("free memory: " + freeMemory / 1024);  
System.out.println("allocated memory: " + allocatedMemory / 1024);  
System.out.println("max memory: " + maxMemory /1024);  
System.out.println("total free memory: " +   
   (freeMemory + (maxMemory - allocatedMemory)) / 1024);