How to know if you have memory size problems or if that's just the JVM growing empty?

The question is the following :

I noticed on my server that the memory is 100% ful开发者_如何学Gol.

Now does that mean that :

• my tomcat needs to much memory, and that I should either optimize my code or add some memory to my server
• the JVM has grown in anticipation of its content growth

The basic question is : should I be worried ?

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run jvisualvm, connect it to your application VM, perform a manual GC and see if there is any memory left?

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..should I be worried ?

Start worrying when the app. gets OutOfMemoryErrors.