OS: RAM (90%) and SWAP (74%) are overloaded. How can it be solved?

Good afternoon. The server uses 2.68 GB of RAM for the needs of the server, mysql, php and other services. You can solve this by turning off the server, then the RAM will not be used. It is the problem that there is no RAM used, since it was created for this. For comparison, my local computer is currently using 10 out of 15 GB of RAM and this does not affect its performance in any way. The same thing with your server, everything is fine with it - it works normally.

Good afternoon.
RAM and SWAP are all server RAM.
Memory is managed by the operating system kernel, if services need memory, the kernel allocates it.
If there are memory pages that are rarely used, the OS kernel can move those pages to SWAP.
You, as a user of the system, cannot influence this process.
If you restart resource-intensive services (like a database example), then memory usage will decrease for a while.
But with active work, the memory will again be used.
Simply put - you can't clean anything to change the system's memory usage.

anonymous duck Tasun Sergey Vladimirovich good. And such entities as actions once a minute / hour / day and the like - also do not affect?

Good afternoon.
Any software that runs on the server uses RAM, including scripts that implement the functionality of automation actions.
If you process any data, then the memory will be used.
If there is no data in your system, then, accordingly, memory will not be needed for its processing.