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📊 Profiling a Spring Boot Application Using VisualVM

This guide walks you through downloading, installing, and using VisualVM to profile a Spring Boot application with enhanced JVM flags for better profiling support.

🧰 Prerequisites

  • Java JDK (8 or higher)
  • Spring Boot project (Maven-based)
  • Maven (mvn) installed
  • VisualVM

🔽 Step 1: Download and Install VisualVM

  1. Visit: https://visualvm.github.io
  2. Download the version for your OS:
    • Windows: .zip or .exe
    • macOS: .dmg
    • Linux: .tar.gz
  3. Extract and run:
    • Windows: visualvm.exe
    • macOS/Linux: ./bin/visualvm

📌 VisualVM may also be included in your JDK as jvisualvm.

⚙️ Step 2: Add Spring Boot Actuator (Optional but Recommended)

To expose runtime metrics in your Spring Boot app, add this to your pom.xml:

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

🚀 Step 3: Run Spring Boot with JVM Profiling Flags

Use the following Maven command to run your Spring Boot app with JVM options enabled for profiling, in Linux:

MAVEN_OPTS="-Dcom.sun.management.jmxremote \
            -Dcom.sun.management.jmxremote.port=9010 \
            -Dcom.sun.management.jmxremote.local.only=false \
            -Dcom.sun.management.jmxremote.authenticate=false \
            -Dcom.sun.management.jmxremote.ssl=false \
            -Djava.rmi.server.hostname=127.0.0.1" \
mvn spring-boot:run

For Windows, use the following command:

set MAVEN_OPTS=-Dcom.sun.management.jmxremote ^
 -Dcom.sun.management.jmxremote.port=9010 ^
 -Dcom.sun.management.jmxremote.local.only=false ^
 -Dcom.sun.management.jmxremote.authenticate=false ^
 -Dcom.sun.management.jmxremote.ssl=false ^
 -Djava.rmi.server.hostname=127.0.0.1
mvn spring-boot:run

These flags allow:

  • -Dcom.sun.management.jmxremote: Enables JMX (Java Management Extensions)
  • -Dcom.sun.management.jmxremote.port=9010: The port VisualVM connects to
  • -Dcom.sun.management.jmxremote.local.only=false: Allows non-local connections (optional if local only)
  • -Dcom.sun.management.jmxremote.authenticate=false: No username/password required
  • -Dcom.sun.management.jmxremote.ssl=false: No SSL needed
  • -Djava.rmi.server.hostname=127.0.0.1: Ensure correct RMI binding (important if issues occur)

🔍 Step 4: Connect to the App in VisualVM

  1. Launch VisualVM
  2. Look under "Local" for your Spring Boot process
  3. Double-click to view monitoring info

📈 Step 5: Start Profiling

Navigate to the tabs:

  • Monitor – CPU, heap, GC, threads
  • Sampler – Low-overhead profiling
  • Profiler – Detailed method-level analysis (more resource-intensive)

Example:

  1. Click Profiler → CPU → Start
  2. Use your app normally
  3. Click Stop to analyze performance

🧠 Step 6: Analyze Results

Check for:

  • Hot methods (high CPU usage)
  • Memory usage by class
  • Thread contention
  • GC overhead

Use insights to refactor and optimize performance.

🌐 Optional: Access Spring Boot Metrics

Add this to application.properties:

management.endpoints.web.exposure.include=*
management.endpoint.metrics.enabled=true

Then access:

http://localhost:8080/actuator/metrics

Example sub-metric (e.g. JVM memory): 👉 http://localhost:8080/actuator/metrics/jvm.memory.used

✅ Summary

Step Description
1 Install VisualVM
2 Add Actuator (optional)
3 Run Spring Boot with JVM flags
4 Connect to app using VisualVM
5 Profile using Sampler/Profiler tabs
6 Analyze and optimize code