GraalVM Project
Goal of this project
Goal of this project is to make KumuluzEE framework compatible with GraalVM.
GraalVM installation
Installation steps are available on GraalVM official site.
Project elements
- Simple service:
- API which return constants
- Servlet which returns constants
- Only one module (no business logic and no DB connectivity)
- Dockerfile for building a docker image
- Folder Dockerfiles contains backups and different type of docker files
Usage
Note: maven-plugin goal has to be set to repackage for uber-jar and to copy-dependencies for exploded.
Running with scripts (EXPLODED)
To execute mvn and tracing agent run trace.sh script.
After tracing run build.sh script in order to build no-fallback image.
After generating image simply run graalvm-basic.
Note: Edit those scripts to fit your needs
Manually - UBER(FAT) JAR
mvn clean package
Use native-image-agent to generate configuration files for native-image (application will start):
java -agentlib:native-image-agent=config-merge-dir=api/src/main/resources/META-INF/native-image -jar api/target/graalvm-basic.jar
Then generate native-image:
sudo native-image --no-fallback \
--allow-incomplete-classpath \
--enable-https \
-H:+JNI \
-H:+PrintClassInitialization \
-H:+ReportExceptionStackTraces \
-H:EnableURLProtocols=http,https,jar,jrt \
-H:ConfigurationFileDirectories=api/src/main/resources/META-INF/native-image/ \
-H:ReflectionConfigurationFiles=api/src/main/resources/META-INF/native-image/reflect-config.json \
-H:ResourceConfigurationFiles=api/src/main/resources/META-INF/native-image/resource-config.json \
-H:JNIConfigurationFiles=api/src/main/resources/META-INF/native-image/jni-config.json \
-jar api/target/graalvm-basic.jar
If everything is done right, you should be able to start native-image:
./graalvm-basic
Manually - EXPLODED
mvn clean package
Use native-image-agent to generate configuration files for native-image (application will start):
sudo java -agentlib:native-image-agent=config-output-dir=api/src/main/resources/META-INF/native-image -cp api/target/classes:api/target/dependency/* com.kumuluz.ee.EeApplication
Then generate native-image:
sudo native-image --no-fallback \
--allow-incomplete-classpath \
--enable-https \
-H:+JNI \
-H:+PrintClassInitialization \
-H:+ReportExceptionStackTraces \
-H:EnableURLProtocols=http,https \
-H:ConfigurationFileDirectories=api/src/main/resources/META-INF/native-image/ \
-H:ReflectionConfigurationFiles=api/src/main/resources/META-INF/native-image/reflect-config.json \
-H:ResourceConfigurationFiles=api/src/main/resources/META-INF/native-image/resource-config.json \
-H:JNIConfigurationFiles=api/src/main/resources/META-INF/native-image/jni-config.json \
-cp api/target/classes:api/target/dependency/* com.kumuluz.ee.EeApplication \
graalvm-basic
If everything has been done right, you should be able to start native-image:
./graalvm-basic
Known (potential) errors
- Resource web.xml is not included in generated image. Issue opened on GraalVM Github may help, though it is not solved.
Boot time comparison
All tests were executed on virtual machine with 8 vCPU and 64GB RAM.
Each time in table represents an avarage time of 100 boots (in milliseconds). Times are saved in time_tests folder.
| Project | Time to boot in JVM | Fallback image | No-fallback image |
|---|---|---|---|
| this project | 1787 ms | 1832 ms | / |
| fri-pointer | 7832 ms | 8347 ms | / |
Useful links
- Class initialization in Native Image
- Github - JakaBernard/graalvm-diploma-aplikacija
- Github - Oracle/GraalVM/native-image-limitations
- Medium - Updates on Class Initialization in GraalVM Native Image Generation
- Introducing the Tracing Agent: Simplifying GraalVM Native Image Configuration
- InfoQ - GraalVM 20.0: Run Tomcat as Native Image on Windows
- Apache - Tomacat 9 GraalVM support
Forums/Issues
- Github - Service loader error
- Github Issue - Error building Scala project with native-image
- Stackoverflow - Can't find bundle for base name /Bundle