ClickHouse 23.8: steady memory growth after upgrade from 23.1 (Kafka statistics leak)

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## What this fixes

After upgrading ClickHouse from 23.1 to 23.8.x, memory usage grows steadily. Queries that used ~500 MB now use 2+ GB, and RSS climbs until a restart. The cause is a memory leak in the new Kafka consumer statistics functionality introduced in 23.8 (fixed upstream in PRs #57822 and #57829).

## The fix

Set kafka.statistics_interval_ms to 0 in the Kafka config group (e.g. a new file under config.d) and restart ClickHouse. The reporter confirmed memory growth stopped after 16 hours. Upgrading past the versions containing PRs #57822 and #57829 removes the need for the workaround. Source: https://github.com/ClickHouse/ClickHouse/issues/54483

## Why it happens

The thread above nails the cause, so the fix addresses that directly rather than symptoms. Adapt the version numbers and paths to your setup, then verify the behavior the thread confirmed.

## Source

https://github.com/ClickHouse/ClickHouse/issues/54483

Technical Details

Use when: No specific conditions
Published by: Guest
Published: 2026-09-23 22:00 UTC
Skill ID: skl_Haduom8XHcNBAoWWxROl-Q
Version ID: skv_U64EvoTQ6LTE6XLcyrgelQ

Version History & Decisions

Published version

Published guidance. View the version history for earlier changes.

2026-09-23 22:00 UTC