Company or project name

Voiceanalytics project

Describe the situation

We observed that with the newer versions, server load increased significantly, while speed decreased.

The system was tested with three different ClickHouse versions (dockerized):

• The same number of queries (100,000 different ones)
• The same query order
• The same database
• Default configuration, only the HTTPS port was modified
• The same hardware

The server load (CPU) is completely different for all three versions:

• clickhouse/clickhouse-server:24.11.1.2557 - load: 9
• clickhouse/clickhouse-server:24.12 - load: 20
• clickhouse/clickhouse-server:25.1.1.4165 - load: 87

The running times (min/sec):

• clickhouse/clickhouse-server:24.11.1.2557 - 6:45
• clickhouse/clickhouse-server:24.12 - 7:20
• clickhouse/clickhouse-server:25.1.1.4165 - 18:20

How to reproduce

• clickhouse/clickhouse-server:24.11.1.2557
• clickhouse/clickhouse-server:24.12
• clickhouse/clickhouse-server:25.1.1.4165

Expected performance

Acceleration or at least similar CPU load is expected.

Additional context

Repeating the test 8 times, we obtained the same speed/load data.