Memory management in Managed Service for ClickHouse®

The amount of RAM available for using ClickHouse® is specified in the Max server memory usage setting.

It also affects the maximum value of the Max memory usage setting.

As opposed to other DBMS settings, you cannot change the Max server memory usage setting value directly. Managed Service for ClickHouse® sets its value automatically depending on the amount of RAM available to ClickHouse® hosts:

• RAM less than 10 GB: Setting value is 1 GB less than the host's RAM.
• RAM more or equal to 10 GB and less than 40 GB: Setting value is 90% of the host's RAM.
• RAM more or equal to 40 GB: Setting value is 4 GB less than the host's RAM.

The remaining RAM is committed to the OS and auxiliary services such as monitoring or backups.

You can only change the Max server memory usage setting value along with the host class.

ClickHouse® is a registered trademark of ClickHouse, Inc.