v.25.11Improvement

If the system memory is lower than

If the system memory is lower than 5GB, don't mlock the executable by default. #89751 (Alexey Milovidov).
By default, ClickHouse will no longer use mlock to lock the executable in memory if the system RAM is below 5GB.

Why it matters

This change prevents potential memory pressure and out-of-memory issues on systems with low RAM by avoiding locking the ClickHouse executable in memory when there is less than 5GB of system memory available.

How to use it

This behavior is applied automatically based on the system memory size. No user action is required to enable this change; it is enabled by default in the new version.