ClickHouse/tests/testflows/aes_encryption/configs/clickhouse/config.d/storage.xml

<clickhouse>

<storage_configuration>
    <disks>
        <default>
            <keep_free_space_bytes>1024</keep_free_space_bytes>
        </default>
    </disks>
    <policies>
        <default>
            <volumes>
                <default>
                    <disk>default</disk>
                </default>
            </volumes>
        </default>
    </policies>
</storage_configuration>

</clickhouse>