Is the Xms/Xmx setting defining the memory space that is allocated outside of the jvm heap? The java executable looks like its set to -Xms256m -Xmx1g. It looks like my command line options do not affect the java memory parameters.
I've also tried exporting ES_MIN_MEM and ES_MAX_MEM but I don't see any differences in the process details.
It is being passed, check at the end of the command. The last memory settings used are the ones that are applied, and the script makes use of that fact. You can easily see the memory settings elasticsearch was started with using the nodes info API.