elasticsearch/docs/reference/modules/indices/query_cache.asciidoc

[[query-cache]]
=== Node Query Cache

The query cache is responsible for caching the results of queries.
There is one queries cache per node that is shared by all shards.
The cache implements an LRU eviction policy: when a cache becomes full, the
least recently used data is evicted to make way for new data.
It is not possible to look at the contents being cached.

The query cache only caches queries which are being used in a filter context.

The following setting is _static_ and must be configured on every data node in
the cluster:

`indices.queries.cache.size`::

    Controls the memory size for the filter cache , defaults to `10%`. Accepts
    either a percentage value, like `5%`, or an exact value, like `512mb`.

The following setting is an _index_ setting that can be configured on a
per-index basis:

`index.queries.cache.enabled`::

    Controls whether to enable query caching. Accepts `true` (default) or
    `false`.