Update graalvm.md

docs/graalvm.md

@@ -158,6 +158,16 @@ In order to use Java or Kotlin plugins on RESTHeart native you must build them a
 
 Refer to [Deploy Java Plugins On Restheart Native](https://restheart.org/docs/plugins/deploy/#deploy-java-plugins-on-restheart-native) for detailed instructions on how to do it.
 
+## build native image
+
+Build image for local OS
+
+```bash
+$ ./mvnw clean package -Pnative -DskipTests
+```
+
+__Note__: Linux needs to use the `G1` garbage collector. This is obtained by passing the `-Dnative.gc="--gc=G1"` property to maven.
+
 ## A docker image to build Linux native images
 
 [SoftInstigate](https://softinstigate.com) maintains the Debian based, docker image [softinstigate/graalvm-maven](https://github.com/SoftInstigate/graalvm-maven-docker) with GraalVM and Maven and `native-image`.
@@ -175,7 +185,9 @@ $ docker run -it --rm \
     -v "$PWD":/opt/app  \
     -v "$HOME"/.m2:/root/.m2 \
     softinstigate/graalvm-maven \
-    clean package -Pnative
+    clean package -Pnative -DskipTests -Dnative.gc="--gc=G1"
 ```
 
+native-image arguments are defined in [this file](https://github.com/SoftInstigate/restheart/blob/master/core/src/main/resources/META-INF/native-image/org.restheart/restheart/native-image.properties).
+
 </div>