The default JVM option for EAP 7.x on OpenShift is ParallelGC. Enabling G1 garbage collection by adding "-XX:+UseG1GC" option gives error "Conflicting collector option used"

To change the GC algorithm, followed the step 1 and 2 which works fine:
1) oc get dc
2) oc env dc/eap70-openshift JAVA_OPTS_APPEND="-XX:-UseParallelGC -XX:+UseG1GC"
where "eap70-openshift" is the dc name

However, this approach may cause issues in future, if there is a requirement to change the GC algorithm again from G1 to any other e.g. CMS. The approach would be similar, disable -XX:-UseG1GC and enable CM algorithm. This will increase the JVM_OPTS options.

Suggestion: Perhaps check if some GC environment variable is set before trying to configure defaults.