avoid OOM by linux kernel co-operative memory management

Allocating sufficiently available memory but not too much has been a challenge for MariaDB and MySQL users for a significant time.

The overallocation results in a risk of OOM killing of the server process.

Linux kernel this interface:
https://www.kernel.org/doc/html/latest/accounting/psi.html

By receiving a memory event of memory pressure options are:

• madvice(DONT_NEED/FREE) on buf_pool.free
• Moving innodb buffer LRU pool chunks to free
• Resizing down innodb buffer pool
• Kill off thread cache thread(s)?
• table caches (are these large?)

So configuration would need a trigger values, "<some|full> <stall amount in us> <time window in us>", from the kernel interface. And a response for "some"/"full".