Clickhouse - GoKawiil

Engineering team cuts ClickHouse query latency from 85 seconds to sub-second

A team tasked with speeding up ClickHouse for its largest customers found a critical dashboard query taking over 85 seconds and scanning nearly 2 billion rows across 198GB of data. Over four months, they applied a series of incremental, non-flashy optimizations—tackling issues like the overhead of ReplacingMergeTree's FINAL clause on mutable event data and an inefficient partition key—to bring the query down to sub-second response times.

jordivillar.com · 2026-09-09

Tinybird engineer details six years of running petabyte-scale ClickHouse clusters

A Tinybird engineer who has operated ClickHouse clusters since version 18.4 nearly six years ago published a detailed retrospective on running the database at petabyte scale. The post walks through the standard shard-and-replica architecture ClickHouse recommends and highlights the operational pitfalls that only surface once a cluster is running in production. Tinybird notes it is an independent contributor to the open-source project and unaffiliated with ClickHouse, Inc.

tinybird.co · 2026-09-07