Good afternoon.
Problems with minute cron, as far as I remember, are mainly related to working with external integrations.
Here
https://1b.app/ru/forum/server-installation/12433-ne-zagurzhayutsya-zakazi-i-pla...I answered you that the stability of the cron, when working with external resources, does not depend on the computing resources of your server.
These are unrelated events.
The operating system sees all 16GB of memory and allocates memory to services and services when they request it.
The system uses RAM as much as it needs at the moment.
A sign that there is enough memory in the system is the minimum use of SWAP memory.
For some services, for example, the database service, it can be configured to use a certain amount of memory.
Scripts are also given a certain amount of memory that they can use.
These settings are configurable.
At the moment, you are not working out minute crowns, because. for it you need to increase the limit, tk. what is allocated to him for today (512Mb) is not enough.
PHP Fatal error: Allowed memory size of 536870912 bytes exhausted (tried to allocate 4096 bytes)