diff --git a/defaults/main.yml b/defaults/main.yml
index 9c31899..38c5e37 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -7,6 +7,11 @@ keycloak_openjdk_version:
   - '{{ keycloak_openjdk_runtime_version }}'
 keycloak_openjdk_bin: '/usr/lib/jvm/java-{{ keycloak_openjdk_runtime_version}}-openjdk-amd64/bin/java'
 keycloak_install_dir: '/opt/keycloak'
+keycloak_java_heap_min: "64m"
+keycloak_java_heap_max: "512m"
+keycloak_java_metaspacesize: "96m"
+keycloak_java_metaspace_max_size: "256m"
+keycloak_java_opts: "-Xms{{ keycloak_java_heap_min }} -Xmx{{ keycloak_java_heap_max }} -XX:MetaspaceSize={{ keycloak_java_metaspacesize }} -XX:MaxMetaspaceSize={{ keycloak_java_metaspace_max_size }} -Djava.net.preferIPv4Stack=true -server -Djava.awt.headless=true -Dfile.encoding=UTF-8"
 keycloak_distribution_data_directory: '{{ keycloak_install_dir }}/{{ keycloak_distribution }}/{{ keycloak_wildfly_mode }}'
 keycloak_conf_directory: '{{ keycloak_runtime_home }}/conf'
 keycloak_providers_directory: '{{ keycloak_runtime_home }}/providers'
diff --git a/templates/keycloak.service.j2 b/templates/keycloak.service.j2
index 6b118d6..592cc30 100644
--- a/templates/keycloak.service.j2
+++ b/templates/keycloak.service.j2
@@ -16,6 +16,7 @@ Before=apache2.service
 [Service]
 Environment=JAVA={{ keycloak_openjdk_bin }}
 Environment=JAVA_HOME=/usr/lib/jvm/java-{{ keycloak_openjdk_runtime_version}}-openjdk-amd64
+Environment=JAVA_OPTS="{{ keycloak_java_opts }}"
 Environment=JAVA_OPTS_APPEND="-Djgroups.mcast_addr={{ keycloak_jgroups_multicast_address}} -Djgroups.mcast_port={{ keycloak_jgroups_multicast_port }}"
 User={{ keycloak_user }}
 Group={{ keycloak_user }}
@@ -24,4 +25,4 @@ UMask=0027
 ExecStart={{ keycloak_runtime_home }}/bin/kc.sh start{% if not keycloak_optimize_build_at_startup %} --optimized{% endif %}{% if keycloak_disabled_features | length %} --features-disabled={% for dis in keycloak_disabled_features %}{{ dis }}{% if not loop.last %},{% endif %}{% endfor %}{% endif %}{% if keycloak_preview_features | length  %} --features={% for feat in keycloak_preview_features %}{{ feat }}{% if not loop.last %},{% endif %}{% endfor %}{% endif %}{% if keycloak_upgrade_db_at_startup %} --spi-connections-jpa-default-migration-strategy=update{% endif %}
 
 [Install]
-WantedBy=multi-user.target
\ No newline at end of file
+WantedBy=multi-user.target