- An Index can be created explicitly using index API
- Number of shards are defined when an index is created
- Number of shards cannot be changed after the index has been created, there is a shrink API with caveats
- The number of replicas can be updated on an existing index:
PUT /index-name/_settings { "number_of_replicas": 5 } - The number of replicas can be configured dynamically:
index.auto_expand_replicas: 0-5 - Query size can be limited to conserve heap memory:
index.max_result_window: 10000 - More index settings