More optimizations on Maven.

Jenkinsfile

@@ -72,7 +72,9 @@ pipeline {
     // see https://jenkins.io/doc/book/pipeline/syntax/#environment
     environment {
         JOB_OPTIONS = "${options}"
-        MAVEN_OPTS="-Dmaven.artifact.threads=16 -T 2C"
+        //make the JVM start a bit faster with basic just-in-time compilation of the code only (-XX:*)
+        //make maven running in a multi-thread fashion (16 threads, 2 threads on each Core)
+        MAVEN_OPTS="-Dmaven.artifact.threads=16 -T 2C -XX:+TieredCompilation -XX:TieredStopAtLevel=1 "
         AGENT_ROOT_FOLDER = "${agent_root_folder}"
         MAVEN_SETTINGS_FILE = "${maven_settings_file}"
         MAVEN_LOCAL_REPO = "${agent_root_folder}/${maven_local_repo_path}"