When I install ES from a .deb package on Ubuntu, it creates /etc/default/elasticsearch with something like this:
ES_HEAP_SIZE=2g ES_MIN_MEM=512m ES_MAX_MEM=2g ES_JAVA_OPTS="-Xmx2048m -Xms512m"
All these things are passed as environment variables inside the actual startup script.
Aren't all those settings redundant? Can I just set ES_HEAP_SIZE and call it a day?
Or do I have to also set -Xmx and -Xms? And if this is the case, do I need to set -Xmx bigger than heap?
How would you change that list of variables, if any changes are required? I'm not talking about the actual heap size and whatnot, but I'm curious whether it makes sense to maintain that list, and how the various values should be correlated, if at all.