# How to optimize my ElasticSearch Query

**URL:** <https://discuss.elastic.co/t/how-to-optimize-my-elasticsearch-query/376531>\
**Category:** Elasticsearch\
**Created:** [March 28, 2025, 2:02pm UTC](https://discuss.elastic.co/t/how-to-optimize-my-elasticsearch-query/376531 "2025-03-28T14:02:10Z")\
**Posts on this page:** 3\
**Page:** 2

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**Author:** ![simon\_Guille](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/simon_guille/32/142316_2.png) [@simon\_Guille](https://discuss.elastic.co/u/simon_Guille)\
**Post date:** [April 4, 2025, 8:36am UTC](https://discuss.elastic.co/t/how-to-optimize-my-elasticsearch-query/376531/21 "2025-04-04T08:36:46Z")

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> [@Christian\_Dahlqvist](#):
>
> That recommendation assumed you were querying a single index. If you are querying multiple indices you may wan to reduce the number of replicas to e.g. 2.

We tried with 2 replicas and we had more errors.

> [@Christian\_Dahlqvist](#):
>
> Start testing with a single concurrent query and then gradually increase the number of concurrent queries until you start seeing errors or get excessive latencies.

Ok I'll try this. Thanks

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**Author:** ![RainTown](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/raintown/32/140206_2.png) [@RainTown](https://discuss.elastic.co/u/RainTown)\
**Post date:** [April 4, 2025, 9:07am UTC](https://discuss.elastic.co/t/how-to-optimize-my-elasticsearch-query/376531/22 "2025-04-04T09:07:22Z")

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… and please keep trying to profile the query.

And I understood you were querying a single index , at least most of the time, right ? Your most recent monthly created index ?

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<div class="post-metadata">

**Author:** ![RainTown](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/raintown/32/140206_2.png) [@RainTown](https://discuss.elastic.co/u/RainTown)\
**Post date:** [April 5, 2025, 11:30pm UTC](https://discuss.elastic.co/t/how-to-optimize-my-elasticsearch-query/376531/23 "2025-04-05T23:30:19Z")

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Another (left field) thought : I notice your generated (complex) query has quite a few should clauses. Lucene can be a bit tricky there. Put another way, it’s possible your query isn’t doing what you _think_ it’s doing, ie it’s logically different to what you expect. Since the query is too complex/nested to parse by eye and anyways I’ve no idea what you are trying to search for, I cannot possible know myself.

I return again to the suggestion to reconstruct the query manually, with ANDs and NOTs and so on, all correctly bracketed. Step by step. Test performance at each step. Performance wise, should clauses can often effectively be just score boosters, so unless query optimiser does perfect job there might be a lot of semi-wasted effort in executing the query.

And this thought might also be off-beam, and if so I apologise.

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