The Elasticsearch configuration settings have changed with each major release; the following matrix shows how they have changed by version.

The "×" cells indicate that the setting is no longer used.

Elasticsearch Settings

Location: /etc/elasticsearch/elasticsearch.yml

Elasticsearch Config Parameters	2.3.3	5.6.12	6.8.6	7.5.2	7.17	8.15

Elasticsearch Config Parameters	2.3.3	5.6.12	6.8.6	7.5.2	7.17	8.15
index.max_result_window		x	x	x	x	x
index.translog.sync_interval		x	x	x	x	x
index.translog.durability		x	x	x	x	x
bootstrap.mlockall		bootstrap.memory_lock
threadpool.bulk.queue_size			thread_pool.write.queue_size		x	x
script.inline script.indexed		script.inline	×	×	×	×
discovery.zen.ping.unicast.hosts				discovery.seed_hosts
discovery.zen.minimum_master_nodes				cluster.initial_master_nodes
action.destructive_requires_name: false	x	×	×	×	×
xpack.security.enabled: false	x	×	×	×	×
xpack.security.enrollment.enabled: false	x	×	×	×	×
xpack.security.http.ssl: enabled: false	x	×	×	×	×
xpack.security.transport.ssl: enabled: false	x	×	×	×	×
ingest.geoip.downloader.enabled: false	x	×	×	×	×
xpack.ml.enabled: false	x	×	×	×	×

Memory Management

Location	Setting	Elasticsearch 2.3.3	5.6.12	6.8.6	7.5.2	7.17	8.15

Location

Setting

Elasticsearch 2.3.3

5.6.12

6.8.6

7.5.2

7.17

8.15

/etc/sysconfig/elasticsearch

ES_HEAP_SIZE

Set to half the physical memory on the
machine, but not more than 31 GB.

×

/etc/elasticsearch/jvm.options

-Xms

-Xmx

x

Set to half the available memory,
but not more than 31 GB.

It’s no longer configured as heap size is automatically determined.