JVM internal memory management

What is JVM default size of Perm space in java ?

default size of Perm space is 64 MB in java.

Java VisualVM [ Heap Dump, Thread Dump, Memory Dump, CPU Dump ] ?

Java VisualVM is a tool that provides a visual interface for viewing detailed information about Java applications while they are running on a Java Virtual Machine (JVM), and for troubleshooting and profiling these applications. 

Tools:

• jvisualvm - the man/manual page for Java VisualVM for Solaris, Linux, or Mac OS X or Windows.
• uses-> open cmd -> type ->  jvisualvm -> enter

Heap dump, Thread dump, Memory dump

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Tuning the Memory Management System in Java

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Memory management or performance in Java

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