# KRaft Controller Disk Size Recommendation

**URL:** <https://forum.confluent.io/t/kraft-controller-disk-size-recommendation/38533>\
**Category:** Ops\
**Created:** [16 October 2026 18:40 UTC](https://forum.confluent.io/t/kraft-controller-disk-size-recommendation/38533 "2026-10-16T18:40:12Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![mdouglas47](https://avatars.discourse-cdn.com/v4/letter/m/c89c15/32.png) [@mdouglas47](https://forum.confluent.io/u/mdouglas47)\
**Post date:** [16 October 2026 18:40 UTC](https://forum.confluent.io/t/kraft-controller-disk-size-recommendation/38533/1 "2026-10-16T18:40:13Z")

</div>

Hello,

I’m doing research to better understand KRaft’s expected resource utilization. I ran into a Confluent doc that provides a recommended disk size of at least 64GB, and I’m looking for help understanding what drives the recommendation.

[Confluent’s documentation](https://docs.confluent.io/platform/7.5/kafka-metadata/config-kraft.html#hardware-and-jvm-requirements) says

> Minimum of 4 GB of RAM
> 
> An SSD disk at least 64 GB in size is highly recommended

[Apache’s KRaft documentation](https://kafka.apache.org/43/operations/kraft/#deploying-considerations) says

> The Kafka controllers store all the metadata for the cluster in memory and on disk. We believe that for a typical Kafka cluster 5GB of main memory and 5GB of disk space on the metadata log directory is sufficient.

Confluent’s RAM minimum is similar to the Apache estimate of KRaft’s RAM use, whereas Confluent’s recommended disk minimum is more than 10x Apache’s estimate of KRaft’s metadata log directory disk use.

Could someone explain what drives the 64 GB recommendation? Is it mainly for operational headroom plus a safety buffer on top of the 5 GB of use expected for KRaft metadata, or is there more to the picture?

Thank you,  
Morgan