JVM config

[Theodore]

Hello, hello,
then I have a small matter related to JVM:
I would like to know if the following command:

java-jar Xmx512m-monProg.jar

do what of the following

1. - Changes in the constant memory of the JVM in allocating 512MB then launches monProg.jar
2. - Or monProg.jar launches with a 512MB memory allocated
3. - Or monProg.jar launches with 512 MB and keeps that value in memory for future launches monProg.jar

thanks for your suggestions

[opaper]

in fact your command will simply run the jar with a maximum of 512MB of memory use and only for the appeal of the order.

[Reegan]

In fact we need to better change the minimum and maximum value to the size:
-Xms512m-Xmx512m

[absolute55]

I do not agree, it depends on the behavior. If you know that your application will use all the time most of the 512 MB, you can follow the advice of reegan , otherwise it is not necessary. Use a profiler to verify that, for example TPTP Eclipse, the NetBeans profiler, JProfiler, YourKit ...