# Why I see fielddata when doc\_value is enabled in Aggregations?

**URL:** https://discuss.elastic.co/t/why-i-see-fielddata-when-doc-value-is-enabled-in-aggregations/158559
**Category:** Elasticsearch
**Created:** [November 28, 2018, 11:55am UTC](https://discuss.elastic.co/t/why-i-see-fielddata-when-doc-value-is-enabled-in-aggregations/158559 "2018-11-28T11:55:57Z")
**Posts on this page:** 4
**Page:** 1

<div class="post-metadata">

### Author: ![Hessam\_Jalali](https://avatars.discourse-cdn.com/v4/letter/h/258eb7/32.png) [@Hessam\_Jalali](https://discuss.elastic.co/u/Hessam_Jalali)
#### Post date: [November 28, 2018, 11:55am UTC](https://discuss.elastic.co/t/why-i-see-fielddata-when-doc-value-is-enabled-in-aggregations/158559/1 "2018-11-28T11:55:57Z")

</div>

Based on [Elastic Documents](https://www.elastic.co/guide/en/elasticsearch/reference/current/doc-values.html), every type except text(an analyzed string) supports `doc_values` which I suppose when available, should completely omit `fielddata` in Aggregation.

However this not the case for me, whenever I do term aggregation based on a `keyword` or `ip` type I see they are loaded as `fieldata`, although this is not happening for other types (e.g **session\_id** as `long` type in this case)

Is this the correct behavior? if true, how can I prevent `fielddata` creation?

I'm using elasticsearch 6.5 and This is my mapping

```
{
  "settings": {
    "index": {
      "number_of_shards": 2,
      "number_of_replicas": 0,
      "codec": "best_compression"
    }
  },
  "mappings": {
    "_doc": {
      "properties": {
        "time": {
          "type": "date",
          "format": "epoch_millis"
        },
        "session_token": {
          "type": "keyword"
        },
        "session_ref": {
          "type": "keyword"
        },
        "session_id": {
          "type": "long"
        },
        "src": {
          "type": "ip"
        },
        "version": {
          "type": "byte"
        }
      }
    }
  }
}

```

this is a sample aggregation which causes `fielddata` to get loaded

```
GET test_ind/_search?size=0
  {
  "aggs" : {
    "by_token":{
      "terms":{ 
        "field": "token",
        "size": 100
      }
    }
  }
  }

```

and here is fielddata status after aggregation

```
"test_ind" : {
  "uuid" : "DiB6d7EgSXm7jeiSgoo-mQ",
  "primaries" : {
    "fielddata" : {
      "memory_size_in_bytes" : 1564696,
      "evictions" : 0,
      "fields" : {
        "session_ref" : {
          "memory_size_in_bytes" : 0
        },
        "session_token" : {
          "memory_size_in_bytes" : 1564696
        }
      }
    }
  },
  "total" : {
    "fielddata" : {
      "memory_size_in_bytes" : 1564696,
      "evictions" : 0,
      "fields" : {
        "session_ref" : {
          "memory_size_in_bytes" : 0
        },
        "session_token" : {
          "memory_size_in_bytes" : 1564696
        }
      }
    }
  }
}

```

and here is segments stat

```
"test_ind" : {
  "uuid" : "DiB6d7EgSXm7jeiSgoo-mQ",
  "primaries" : {
    "segments" : {
      "count" : 8,
      "memory_in_bytes" : 472939,
      "terms_memory_in_bytes" : 423365,
      "stored_fields_memory_in_bytes" : 3504,
      "term_vectors_memory_in_bytes" : 0,
      "norms_memory_in_bytes" : 0,
      "points_memory_in_bytes" : 41598,
      "doc_values_memory_in_bytes" : 4472,
      "index_writer_memory_in_bytes" : 0,
      "version_map_memory_in_bytes" : 0,
      "fixed_bit_set_memory_in_bytes" : 0,
      "max_unsafe_auto_id_timestamp" : -1,
      "file_sizes" : { }
    }
  },
  "total" : {
    "segments" : {
      "count" : 8,
      "memory_in_bytes" : 472939,
      "terms_memory_in_bytes" : 423365,
      "stored_fields_memory_in_bytes" : 3504,
      "term_vectors_memory_in_bytes" : 0,
      "norms_memory_in_bytes" : 0,
      "points_memory_in_bytes" : 41598,
      "doc_values_memory_in_bytes" : 4472,
      "index_writer_memory_in_bytes" : 0,
      "version_map_memory_in_bytes" : 0,
      "fixed_bit_set_memory_in_bytes" : 0,
      "max_unsafe_auto_id_timestamp" : -1,
      "file_sizes" : { }
    }
  }
}

```

---

<div class="post-metadata">

### Author: ![Mark\_Harwood](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/mark_harwood/32/10538_2.png) [@Mark\_Harwood](https://discuss.elastic.co/u/Mark_Harwood)
#### Post date: [November 28, 2018, 12:11pm UTC](https://discuss.elastic.co/t/why-i-see-fielddata-when-doc-value-is-enabled-in-aggregations/158559/2 "2018-11-28T12:11:16Z")

</div>

See Global Ordinals discussion: [Global ordinals performance and size on-heap](https://discuss.elastic.co/t/global-ordinals-performance-and-size-on-heap/158320)  
From there:

> "They are monitored in the `fielddata` stats, we could have a dedicated section but if you don't have any `text` field that loads `fielddata` then the memory reported can be attributed to global ordinals entirely."

---

<div class="post-metadata">

### Author: ![Hessam\_Jalali](https://avatars.discourse-cdn.com/v4/letter/h/258eb7/32.png) [@Hessam\_Jalali](https://discuss.elastic.co/u/Hessam_Jalali)
#### Post date: [November 28, 2018, 2:08pm UTC](https://discuss.elastic.co/t/why-i-see-fielddata-when-doc-value-is-enabled-in-aggregations/158559/3 "2018-11-28T14:08:15Z")

</div>

thanks for the clarification.

---

<div class="post-metadata">

### Author: ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)
#### Post date: [December 26, 2018, 2:08pm UTC](https://discuss.elastic.co/t/why-i-see-fielddata-when-doc-value-is-enabled-in-aggregations/158559/4 "2018-12-26T14:08:25Z")

</div>

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