By default, the JVM will use up to 16Mb of RAM. If your program allocates a lot of memory, you may need to increase this value to give more room to the garbage collector.
When starting the JVM, two parameters can be adjusted to suit your memory needs:
-mx n Sets the maximum size of the memory allocation pool where n is in bytes, appending "m" to n will specified the number in megabytes, for example to set the maximum at 20Mb:
java -mx 20m myApp
. -ms n Sets the startup size of the memory allocation pool, where n is in bytes, appending "m" to n will specified the number in megabytes. The default is 1Mb.
With JDK1.2, that syntax have changed, no space between ms/mx and the value:
java -mx20m myApp