# Increased Read IOPS usage after upgrade from 8.19.3 to 9.1.3

**URL:** <https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-19-3-to-9-1-3/382156>\
**Category:** Elasticsearch\
**Created:** [September 23, 2025, 9:52am UTC](https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-19-3-to-9-1-3/382156 "2025-09-23T09:52:41Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Paulo\_Guedes](https://avatars.discourse-cdn.com/v4/letter/p/c4cdca/32.png) [@Paulo\_Guedes](https://discuss.elastic.co/u/Paulo_Guedes)\
**Post date:** [September 23, 2025, 9:52am UTC](https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-19-3-to-9-1-3/382156/1 "2025-09-23T09:52:42Z")

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Hi all, since upgrading from 8.19.3 to 9.1.3 i'm seeing a massive increase of read IOPS on the Hot node disks.  
I couldn't see anything obvious in the release notes that would lead to this outside of the new JDK version and new Lucene version.  
Here's a screenshot of it:

 ![image](https://us1.discourse-cdn.com/elastic/original/3X/1/b/1be784d3bb9ced60e1a736b116faebceab40a12b.png)

This is now throwing NodeMemoryMajorPagesFaults from Prometheus. I have checked that I am not doing any force merges on the Hot nodes (I ran GET \_tasks) and I am running 64GB machines with 31GB of heap (I check the VM flags and I have confirmed that it is running with “UseCompressedOops”).

I also noticed that, the warm nodes have increased the average IO/s from 80 to 120 IO/s but the cold nodes have not.

Has anyone noticed similar behaviour? Nothing changed from our side except the version

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<div class="post-metadata">

**Author:** ![erikg](https://avatars.discourse-cdn.com/v4/letter/e/91b2a8/32.png) [@erikg](https://discuss.elastic.co/u/erikg)\
**Post date:** [September 23, 2025, 5:34pm UTC](https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-19-3-to-9-1-3/382156/2 "2025-09-23T17:34:40Z")

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I am not sure if related, but I think in 9.x they enabled logsdb automatically, it’s mentioned that with logsdb you save storage, but there’s a performance overhead

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<div class="post-metadata">

**Author:** ![Paulo\_Guedes](https://avatars.discourse-cdn.com/v4/letter/p/c4cdca/32.png) [@Paulo\_Guedes](https://discuss.elastic.co/u/Paulo_Guedes)\
**Post date:** [September 24, 2025, 12:39pm UTC](https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-19-3-to-9-1-3/382156/3 "2025-09-24T12:39:43Z")

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I executed:

```auto
GET /*/_settings?filter_path=**.settings.index.mode

```

I saw that no index is using the mode “LogsDB”

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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:** [September 25, 2025, 1:37pm UTC](https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-19-3-to-9-1-3/382156/4 "2025-09-25T13:37:31Z")

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We had similar thread before, which sadly did not reach a conclusion:

> [@Increased Read IOPS usage after upgrade from 8.18.0 to 9.0.1](https://discuss.elastic.co/t/increased-read-iops-usage-after-upgrade-from-8-18-0-to-9-0-1/377986):
>
> Hi all, since upgrading from 8.18.0 to 9.0.1 i'm seeing a massive increase of read IOPS on the data node disks. I couldn't see anything obvious in the release notes of 8.18.1, 9.0.0 and 9.0.1 that would lead to this. Here's a screenshot of it: Has anyone experienced the same or knows if it is a known issue - or even expected?

I made some comments in that thread, which may or not have been helpful there, and same applies here.