[[norms]] === `norms` Norms store various normalization factors -- a number to represent the relative field length and the <> setting -- that are later used at query time in order to compute the score of a document relatively to a query. Although useful for scoring, norms also require quite a lot of memory (typically in the order of one byte per document per field in your index, even for documents that don't have this specific field). As a consequence, if you don't need scoring on a specific field, you should disable norms on that field. In particular, this is the case for fields that are used solely for filtering or aggregations. TIP: The `norms.enabled` setting must have the same setting for fields of the same name in the same index. Norms can be disabled on existing fields using the <>. Norms can be disabled (but not reenabled) after the fact, using the <> like so: [source,js] ------------ PUT my_index/_mapping/my_type { "properties": { "title": { "type": "string", "norms": { "enabled": false } } } } ------------ // AUTOSENSE NOTE: Norms will not be removed instantly, but will be removed as old segments are merged into new segments as you continue indexing new documents. Any score computation on a field that has had norms removed might return inconsistent results since some documents won't have norms anymore while other documents might still have norms. ==== Lazy loading of norms Norms can be loaded into memory eagerly (`eager`), whenever a new segment comes online, or they can loaded lazily (`lazy`, default), only when the field is queried. Eager loading can be configured as follows: [source,js] ------------ PUT my_index/_mapping/my_type { "properties": { "title": { "type": "string", "norms": { "loading": "eager" } } } } ------------ // AUTOSENSE TIP: The `norms.loading` setting must have the same setting for fields of the same name in the same index. Its value can be updated on existing fields using the <>.