How to change Elasticsearch max memory size

Question

I have an Apache server with a default configuration of Elasticsearch and everything works perfectly, except that the default configuration has a max size of 1GB.

I

Answer 1

If you use the service wrapper provided in Elasticsearch's Github repository, found at https://github.com/elasticsearch/elasticsearch-servicewrapper, then the conf file at elasticsearch-servicewrapper / service / elasticsearch.conf controls memory settings. At the top of elasticsearch.conf is a parameter:

set.default.ES_HEAP_SIZE=1024

Just reduce this parameter, say to "set.default.ES_HEAP_SIZE=512", to reduce Elasticsearch's allotted memory.

Note that if you use the elasticsearch-wrapper, the ES_HEAP_SIZE provided in elasticsearch.conf OVERRIDES ALL OTHER SETTINGS. This took me a bit to figure out, since from the documentation, it seemed that heap memory could be set from elasticsearch.yml.

If your service wrapper settings are set somewhere else, such as at /etc/default/elasticsearch as in James's example, then set the ES_HEAP_SIZE there.