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Message:

Heap Size increase ...

Posted by Ajjaiah BM on November 27, 2001 at 1:43 PM

Hi,
The OutOfMemory exception may be due to two reasons :
1> JavaHeap is full , can't grow further.
2> NativeHeap is full , can't grow further.

I guess you have already found that your application needs more JavaHeap size , here are some tips how to do that.
You should use the non standard java command line options :

-Xmsn
Specify the initial size, in bytes, of the memory allocation pool. This value must be a multiple of 1024 greater than 1MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 2MB. Examples:

-Xms6291456
-Xms6144k
-Xms6m

-Xmxn
Specify the maximum size, in bytes, of the memory allocation pool. This value must a multiple of 1024 greater than 2MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 64MB. The upper limit for this value will be approximately 4000m on Solaris 7 and Solaris 8 SPARC platforms and 2000m on Solaris 2.6 and x86 platforms, minus overhead amounts. Examples:

-Xmx83886080
-Xmx81920k
-Xmx80m

-Xssn
Set thread stack size. Each Java thread has two stacks: one for Java code and one for C code. This option sets the maximum stack size that can be used by C code in a thread to n. Every thread that is spawned during the execution of the program passed to java has n as its C stack size. The default units for n are bytes and n must be > 1000 bytes. To modify the meaning of n, append either the letter k for kilobytes or the letter m for megabytes. The default stack size is 512 kilobytes (-Xss512k).

I hope this will help ...

Cheers,
Ajjauah BM