# OpenSearch query response time not consistent

**URL:** <https://forum.opensearch.org/t/opensearch-query-response-time-not-consistent/16594>\
**Category:** OpenSearch\
**Tags:** discuss, configure, observability\
**Created:** [November 8, 2023, 12:24pm UTC](https://forum.opensearch.org/t/opensearch-query-response-time-not-consistent/16594 "2023-11-08T12:24:53Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![hemant](https://avatars.discourse-cdn.com/v4/letter/h/cab0a1/32.png) [@hemant](https://forum.opensearch.org/u/hemant)\
**Post date:** [November 8, 2023, 12:24pm UTC](https://forum.opensearch.org/t/opensearch-query-response-time-not-consistent/16594/1 "2023-11-08T12:24:53Z")

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**Versions** (relevant - OpenSearch/Dashboard/Server OS/Browser): OpenSearch - v 2.11.0

**Describe the issue** : We are doing performance Test on Opensearch with following configuration  
OS - m5.2xlarge  
Ram - 32gb  
CPU - 8  
Using 2 nodes and JVMs -16GB (node 1 - 8GB node -2- 8GB. We are running same query with 30 concurrent users by using JMeter. with zero ramp up time. every time response time changing, we have seen 2 sec differences in two runs. there is not any real-time update on OpenSearch data. please suggest how we can get consistent result.

**Configuration** :  
OS - m5.2xlarge  
Ram - 32gb  
CPU - 8

**Relevant Logs or Screenshots** :

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**Author:** ![radu.gheorghe](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.opensearch.org/radu.gheorghe/32/3516_2.png) [@radu.gheorghe](https://forum.opensearch.org/u/radu.gheorghe)\
**Post date:** [November 9, 2023, 7:20am UTC](https://forum.opensearch.org/t/opensearch-query-response-time-not-consistent/16594/2 "2023-11-09T07:20:52Z")

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If you have 0 ramp up time, the state of your operating system and opensearch-related caches will impact performance by a lot.

You’ll probably want to do a “warming up” run just to keep your caches in a comparable state.

Also, I’d suggest monitoring OpenSearch and checking what happens during your test run. If you don’t have a good monitoring tool, let me shamelessly plug ours 🙂 [OpenSearch Monitoring Integration](https://sematext.com/docs/integration/opensearch/)