Boost Spring Boot Performance with GraalVM Native Image: A Step‑by‑Step Guide

GraalVM is a high‑performance virtual machine that can significantly improve program performance and is well suited for micro‑services. The Java framework Quarkus supports GraalVM out of the box, and Spring Boot 2.4 also adds GraalVM support to enhance startup time, memory usage and response latency.

The latest community version of GraalVM (20.3.0) is based on OpenJDK 8u272 and 11.0.9. The recommended way to install and switch JDK versions is SDKMAN, similar to nvm for Node.js.

sdk install java 11.0.9.hs-adpt
sdk default java 11.0.9.hs-adpt

After installation, verify the version:

~ java -version
openjdk version "11.0.9" 2020-10-20
OpenJDK Runtime Environment GraalVM CE 20.3.0 (build 11.0.9+10-jvmci-20.3-b06)
OpenJDK 64‑Bit Server VM GraalVM CE 20.3.0 (build 11.0.9+10-jvmci-20.3-b06, mixed mode, sharing)

Install the native‑image component using the GraalVM gu tool:

# change to JDK bin directory
cd $JAVA_HOME/bin/
# install native-image
./gu install native-image

Create a Spring Boot 2.4 demo project with Spring Initializr, then measure the baseline startup time (≈1135 ms) and memory usage (≈480 MB) for the plain JAR.

Add the required dependencies for GraalVM native compilation (spring‑graalvm‑native, spring‑context‑indexer, and the Spring Milestones repository) and set @SpringBootApplication(proxyBeanMethods = false). Build the native executable with Maven: mvn -Pnative package The resulting native binary com.example.demo.demoapplication starts in about 0.215 seconds and uses only ~24.8 MB of memory.

Without GraalVM: memory 480.965 MB, startup 1135 ms

With GraalVM: memory 24.8203 MB, startup 215 ms