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JVM Performance Basics

? JVM Performance Basics

? Quick Overview

The Java Virtual Machine (JVM) is responsible for executing Java programs efficiently. Understanding JVM performance basics helps developers write faster, memory-efficient, and scalable Java applications.

? Key Concepts

  • JVM Memory Structure
  • Garbage Collection (GC)
  • Just-In-Time (JIT) Compilation
  • Heap vs Stack Memory
  • Performance Tuning Options

? Interactive Heap & GC Simulator

Click Allocate to fill Heap Memory. When it gets full, run Garbage Collection.

 
 
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? Syntax / Theory

The JVM converts bytecode into machine code using the JIT compiler. Memory is divided into heap (objects) and stack (method calls). Garbage collectors automatically clean unused objects to free memory.

? Code Example(s)

? View Code Example
// Simple program to observe JVM memory behavior
public class JVMBasics {
    public static void main(String[] args) {
        String data = "JVM Performance";
        System.out.println(data);
    }
}

? Live Output / Explanation

Output

JVM Performance

The JVM loads the class, allocates memory for objects, executes bytecode, and prints the output to the console.

✅ Tips & Best Practices

  • Use proper JVM memory options like -Xms and -Xmx
  • Avoid unnecessary object creation
  • Choose the right garbage collector
  • Profile applications before optimizing

? Try It Yourself

  • Run a Java program with different heap sizes
  • Enable GC logs and analyze them
  • Compare performance with different JVM flags