Clear ClickHouse filesystem cache between cold runs in datalake benchmarks#821
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alexey-milovidov merged 1 commit intomainfrom Mar 22, 2026
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…marks The benchmarks drop the OS page cache before each query group, but the ClickHouse filesystem cache in `/dev/shm/clickhouse/` was not being cleared. This made cold run numbers unreliable — data cached by the filesystem cache from previous queries survived across runs, making cold times appear much faster than they actually are. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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The benchmarks drop the OS page cache before each query group, but the ClickHouse filesystem cache in
/dev/shm/clickhouse/was not being cleared. This made cold run numbers unreliable — data cached by the filesystem cache from previous queries survived across runs, making cold times appear much faster than they actually are.