Tencent technical customer feedback reply is as follows:

Looking at the server, there doesn't seem to be any major issues. There is an increase in memory scan counts, which is usually caused by high memory pressure. You can keep an eye on this going forward. If there is lag but no abnormality in monitored memory, it means some cache is occupying memory. You can execute during off-peak hours
echo 3 > /proc//sys/vm/drop_caches to release memory (may cause brief jitter), and set vm.min_free_kbytes to 1% of total memory (for reference only)

How to set vm.min_free_kbytes

The vm.min_free_kbytes parameter is set to ensure that the system has enough free memory to handle emergency situations under high memory usage, preventing issues caused by insufficient memory. Setting vm.min_free_kbytes to 1% of total memory is a common practice, but the actual value can be adjusted based on specific circumstances.

To set the vm.min_free_kbytes parameter, you can do so by editing the system's kernel parameters. Typically, this can be accomplished by editing the /etc/sysctl.conf file. The following are the steps to set vm.min_free_kbytes:

1. Open the terminal and log in as root or a user with administrator privileges.
2. Edit the /etc/sysctl.conf file. You can open it using a text editor, for example: Insert code Copy code sudo nano /etc/sysctl.conf
3. Add the following line to the file to set the vm.min_free_kbytes value to 1% of total memory: Insert code Copy code vm.min_free_kbytes = 1% * (total memory) Please replace "1%" with the actual percentage value and replace "(total memory)" with the total memory size of the system. For example, if the system has a total memory of 4 GB, you can set it as: vm.min_free_kbytes = 40M This will set vm.min_free_kbytes to 40 megabytes.
4. Save the file and exit the editor.
5. Apply new kernel parameter settings: sudo sysctl -p

This will make the new vm.min_free_kbytes setting take effect.

Please note that the value of vm.min_free_kbytes should be adjusted based on the specific conditions and requirements of the system. If the system's memory configuration or application resource demands change, this value may need to be reassessed and adjusted. Additionally, before modifying any system parameters, be sure to back up the configuration file just in case.