title: ElasticSearch normalizer performance impact
body: <p>We would like to use normalizers to be able to do case insensitive queries to elastic.</p>
  
  <pre><code>"analysis": {
       "normalizer": {
          "custom_analyzer": {
             "type": "custom",
             "filter": [
                "lowercase"
             ]
          }
       }
    }
  </code></pre>
  
  <p>Which is the performance in the queries operations using normalizers in our Keyword properties?</p>
  
  <p>Reading documentation explains during index building it applies the normalizers to the set properties (I guess most of the work is doing during index building) but documentation says some more operations are done when data is queried.</p>
  
  <p>The operations when data is queried is just to normalize the query text, or is doing something more? Which is the performance impact using normalizers?</p>
  
  <p>Thanks</p>