garbage collection batch job jvm arguments

Question

We have following jvm arguments while running batch jobs. These arguments are specific to ibm jdk 8. What are the corresponding variables for open jdk 8?

<jvmSettings>
<maxMemorySize>6144m</maxMemorySize>
<extraArguments>
<extraArgument>-D64</extraArgument>
<extraArgument>-Xgcpolicy:gencon</extraArgument>
</extraArguments>
</jvmSettings>