[[modules-fielddata]] === Field data cache settings The field data cache is used mainly when sorting on or computing aggregations on a field. It loads all the field values to memory in order to provide fast document based access to those values. The field data cache can be expensive to build for a field, so its recommended to have enough memory to allocate it, and to keep it loaded. The amount of memory used for the field data cache can be controlled using `indices.fielddata.cache.size`. Note: reloading the field data which does not fit into your cache will be expensive and perform poorly. `indices.fielddata.cache.size`:: (<>) The max size of the field data cache, eg `30%` of node heap space, or an absolute value, eg `12GB`. Defaults to unbounded. Also see <>. [discrete] [[fielddata-monitoring]] ==== Monitoring field data You can monitor memory usage for field data as well as the field data circuit breaker using <>