Enhance mapping explosion documentation in Elasticsearch #4539
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- Expanded explanation of mapping explosion in Elasticsearch, including its causes, symptoms, and how to check for issues. - Added details on the default field limit and its implications for performance. - Replaced the intro to avoid the curse of knowledge (intro assumed customer's knew what mappings and field types were).
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yetanothertw
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Thank you for making these changes, they look great!
I've left a couple of small style suggestions for your consideration.
Co-authored-by: Vlada Chirmicci <[email protected]>
Co-authored-by: Vlada Chirmicci <[email protected]>
Co-authored-by: Vlada Chirmicci <[email protected]>
stefnestor
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Jan 7, 2026
stefnestor
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stefnestor
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Co-authored-by: Stef Nestor <[email protected]>
Co-authored-by: Stef Nestor <[email protected]>
Co-authored-by: Stef Nestor <[email protected]>
stefnestor
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| # Mapping explosion [mapping-explosion] | ||
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| {{es}}'s search and [{{kib}}'s discover](../../explore-analyze/discover.md) Javascript rendering are dependent on the search’s backing indices total amount of [mapped fields](elasticsearch://reference/elasticsearch/mapping-reference/field-data-types.md), of all mapping depths. When this total amount is too high or is exponentially climbing, we refer to it as experiencing mapping explosion. Field counts going this high are uncommon and usually suggest an upstream document formatting issue as [shown in this blog](https://www.elastic.co/blog/found-crash-elasticsearch#mapping-explosion). | ||
| In Elasticsearch, a mapping or [mapped field](elasticsearch://reference/elasticsearch/mapping-reference/field-data-types.md) defines the fields in an index and their data types, such as text for full-text search, keyword for exact filtering, or boolean for true/false values. Think of it as a schema that tells Elasticsearch how to interpret and store each piece of data. When the total number of mapped fields across an index grows excessively large, the cluster can experience performance degradation such as slower searches, high heap usage, and prolonged startup times. |
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| In Elasticsearch, a mapping or [mapped field](elasticsearch://reference/elasticsearch/mapping-reference/field-data-types.md) defines the fields in an index and their data types, such as text for full-text search, keyword for exact filtering, or boolean for true/false values. Think of it as a schema that tells Elasticsearch how to interpret and store each piece of data. When the total number of mapped fields across an index grows excessively large, the cluster can experience performance degradation such as slower searches, high heap usage, and prolonged startup times. | |
| In Elasticsearch, a mapping or [mapped field](elasticsearch://reference/elasticsearch/mapping-reference/field-data-types.md) defines the fields in an index and their data types, such as text for full-text search, keyword for exact filtering, or boolean for true/false values. Think of it as a schema that tells Elasticsearch how to interpret and store each piece of data. |
This is now included in the paragraph after it.
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Summary
As part of @stefnestor 2026 Support KB alignment project took the latest information on mapping explosions and filled in to our existing troubleshooting documentation.
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