Hi Everyone, we have an Elasticsearch index with 100 million documents (with replicas it's about 400 million). The index contains nested documents as well. We have a use case where we have to boost the score of the documents using some fields present in the document. For this boosting we are using …

I think disk IOPS was the bottleneck for us. We had some very heavy documents (about 35 - 40MB) in size. Their retrieval was really slow. What we ended up doing was to disable their storage (nested fields) from the _source field. We didn't really need them to be returned in the response but needed …

Elastic Search Query performance when source is disabled

Elastic Stack Elasticsearch

Christian_Dahlqvist (Christian Dahlqvist) October 27, 2022, 6:15am 11

Run the command iostat -x from the command line on the host when queries are slow. This should show you if storage might be an issue.

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Elastic Search Query performance when source is disabled

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