outOFMemoryException.

[madhu Chitloore]

Hi,
I have 90mb xml file where i am parsing that xml using DOM ... and i am getting out of memory exception ... can anyone tell me the solution for this ??? and i cant use SAX parser for my application ...

Thanks,

[Nitesh Kant]

The simplest solution is to increase the JVM heap size if possible. (90 MB of data must not create that much of a problem.)
You can increase the heap size by setting the following JVM parameters:

-Xms<size> (Initial heap size)
-Xmx<size> (Maximum heap size)

[madhu Chitloore]

But i have tried even that : -Xmx1024mb .... its giving same error : outOfMemoryException !...


Thank you for your reply....

[Ben Souther]

"madhu cm",
Please check your private messages regarding an important administrative matter.
-Ben

[William Brogden]

If you get an out of memory exception with large settings, there is probably a conceptual error in your code.

If this was my problem I would start by inserting System.out.println() statements giving current memory use in order to find out how far the program gets. See the java.lang.Runtime JavaDocs.

Bill

[Nitesh Kant]

William:
If this was my problem I would start by inserting System.out.println() statements giving current memory use in order to find out how far the program gets.

At the first look i thought: "Why do i have to put system.out, wont the stack trace give me the point till where it went!"
After a minute i got the answer myself, so thought i will post the same. (Both with an intent of confirmation and sharing)
Actually, OutOfMemory error will occur when JVM is not able to allocate new memory. The stack trace will tell the line where the memory allocation failed and it is not necessay that the line before that was the one where the last memory allocation happened. So, it is very difficult to determine "till where the program went" because the last memory allocation can be anywhere in the code and may be the same line which threw the OutOfMemoryError.

You may also try taking a heap dump using jmap and then analyse it using jhat to know what objects are taking the most of heap space.
By the way, there a lot of profiling tools available like JProbe, JProfiler that will help you if you want to do an advanced profiling.
[ May 19, 2008: Message edited by: Nitesh Kant ]

[William Brogden]

Note that the point at which the memory exception is thrown may well have absolutely nothing to do with the part of the program that contains the conceptual error causing it to hold on to objects and waste memory. Therefore the suggestion of printing memory use statistics at various points.

Bill